Abstract Book

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

Invited Talks

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-01: INDUS BEAMLINES: A BRIEF OVERVIEW

Tapas Ganguli Synchrotron Utilization Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India Email: [email protected] Indus-1 and Indus-2 are the only two synchrotron radiation sources in the country. There are 14 operational beamlines in Indus-2 and two more will be added in this list shortly. There are 7 operational beamlines on Indus-1. All these beamlines are national facilities and are in use by researchers and students from all over the country. There were 855 user experiments carried out at the Indus beamlines in the calendar year 2018 with 167 publications in peer reviewed international journals. The present talk gives a brief highlight of the facilities at the beamlines and some of the interesting research works that have been carried out using these beamlines.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-02: Indus Synchrotron Related Research Activities at UGC-DAE CSR, Indore: A Review D. M. Phase, Mukul Gupta, R. J. Choudhary UGC-DAE Consortium for Scientific Research, DAVV Campus, Khandwa Road, Indore The Angle Integrated Photoemission (AIPES) Beamline developed by consortium scientists has been operational on Indus-1 synchrotron source since year 2000 and users have been doing valence band spectroscopy (VBS) experiments at this beamline. The use of AIPES beamline has taken a quantum jump after consortium scientists initiated work on resonant photoemission spectroscopy which is also reflected by a number of research papers (~ 100) published in high impact journals using this facility. Second major effort in this direction is development of Polarised light soft X-ray absorption spectroscopy (SXAS) beamline on Indus-2 bending magnet synchrotron radiation source. The energy range of this beamline is 100 eV to 1200 eV and one can measure the soft X-ray absorption. Many more group has utilized these exceptional facilities and several good publications have resulted in reputed international journals. Looking at the possibility of selecting the polarization of incoming beam, an experimental station for X-ray Magnetic Circular Dichroism (XMCD) measurements is developed by the consortium scientists; which has brought the SXAS beamline to a next level where the researchers from the country can proudly produce XMCD experiments in-house. This new addition of XMCD measurement facility which is unique in the country, is going to be a very powerful unified tool for materials science research community in the country to probe and comprehend the microscopic origin of various magnetic phenomena. During this talk I will discuss several scientific goals achieved at different stages of this important developmental programme of the consortium.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-03: Hard X-ray absorption spectroscopy with Indus-2 SRS

Ravikumar, Abharana N., N. Patra, A. Diwedi, A.K. Yadav, P. Rajput, C. Nayak, A. Agrawal, A.K. Poswal, D. Bhattacharyya* and S. N. Jha Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai-400 085, India *E-mail: [email protected]

The hard X-ray Absorption Spectroscopy (XAS) measurement facility at Indus-2 SRS consists of two operational beamlines which have been setup at bending magnet ports of Indus- 2, namely: Energy Dispersive EXAFS beamline (BL-08) [1] and Energy Scanning EXAFS beamline (BL-09) [2]. The dispersive EXAFS beamline (BL-08) uses a Si (111) crystal bent in the form of an ellipse in such a fashion that the synchrotron source and the sample are situated at the two focii of the ellipse so that all rays emerging from the source get focussed at the sample position after getting reflected from the crystal. Using this technique, EXAFS measurements can be carried out on various kind of samples in transmission mode in a time scale of 350 msec using a position sensitive detector, which is ideal for studying time resolved processes e.g., catalytic reactions. Since the above beamline has the limitation that samples can only be measured in transmission mode, it posed some restrictions for XAS measurements on dilute samples and samples deposited on thick substrates. Thus subsequently another Energy Scanning-type EXFAS beamline (BL-09) has been developed in at Indus-2 SRS where, using monochromatic beam from a Double Crystal Monochromator, measurements can also be possible in fluorescence mode and the two EXAFS beamlines act as complementary to each other. The two beamlines are equipped with XAS measurement facility over large temperature range of 5.4K-1000K. Since their commissioning the above two hard X-ray XAS beamlines at Indus-2 are in very high demand by users and utilization of the beamlines has resulted into more than 175 journal publications. Research groups from all over the country including national institutes, IITs, universities, and industrial organization and few groups from abroad have used these facilities to characterise their samples having applications in the field of functional materials, nuclear materials, magnetic materials, catalysis, biological science etc. This talk will give glimpses of the various types of research works that have been carried out in the above beamlines in last few years. In the last few years several new facilities have also been added in these beamlines for carrying out state-of-art XAS experiments which include in-situ measurement facility on catalytic and photo-catalystic reactions with high temperature reaction cell with photo- illumination facility and on-line monitoring by gas chromatograph facility [3], simultaneous XAS and UV-Vis spectroscopy measurement facility for monitoring growth of nanoparticles from solution phase, facility for doing in-situ XAS measurements on electrochemical reactions and during charging/discharging of Li & Na ion batteries, grazing incidence XAS measurement facility to carry out depth dependent XAS measurements on thin films and multilayers and hard X-ray-ray magnetic circular dichroism (XMCD) measurement facility for characterization of magnetic samples [4]. A brief overview of the above facilities will also be covered in this talk.

1. Bhattacharyya et.al., Nucl. Instrum. Meth. Phys. Res. A 609 (2009) 286. 2. Basu et.al., J. Phys.: Conf. Ser., 493 (2014) 012032. 3. Nayak et.al., J. Synchrotron Rad. 26 (2019) 137. 4. Patra et.al. J. Synchrotron Rad. 26 (2019) 445. 6

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-04: Potentials and perspectives of ADXRD beamline @Indus 2, BL-12

Archna Sagdeo1,2, Anuj Upadhyay1, Abhay Bhisikar1, M. N. Singh1 and A. K. Sinha1,2 1Synchrotron Utilization Section, Raja Ramanna Centre of Advanced Technology, Indore-452013, India; 2 Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai- 400094,India [email protected]

ADXRD Beamline, BL-12, Indus-2 Angle dispersive x-ray diffraction (ADXRD) is a basic non-destructive technique for determination of crystal structure of any material. Energy tunability and high flux are added advantages in using synchrotron radiation (SR) source for ADXRD technique. Angle dispersive X-ray diffraction beamline has been commissioned @ Indus-2 way back in 2010 and since then various important and interesting studies have been carried out using the ADXRD facilities. The beamline has been used for wide range of experiments like powder and single crystal diffraction; grazing incidence diffraction, x-ray absorption near edge structure and Anomalous XRD at ambient and non-ambient temperature and pressures. The beamline is being utilized by users from Indian universities and research institutions. Here, potentials of ADXRD facilities and summary of some of the important results will be presented.

References

[1] A. K. Sinha, Archna Sagdeo et al., Journal of Physics: Conference Series, Volume 425, Part 7, 072017 (2013).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-05: Plasmons for efficient light harvesting towards ultrathin photovoltaic applications

Vivek Garga, Brajendra S. Sengara, Shailendra Kumarb, Shaibal Mukherjeea, * aHybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology Indore, Madhya Pradesh 453552, India bUniversity Grants Commission, Department of Atomic Energy (UGC DAE), Consortium for Scientific Research, Indore, Madhya Pradesh 452017, India *E-mail: [email protected]

Indus beamline(s) Used: AIPES beam line Indus facility at RRCAT

Recently, the realization of ultrathin solar cells is the area of interest of researchers in the domain of cost-effective photovoltaics. This study demonstrates a novel way of generation of plasmonic features in various locations of a solar cell architecture such as absorber material, buffer layer, and transparent conducting oxide material to compensate for the loss of optical absorption due to reduced absorber thickness. Through an extensive analysis of photoelectron spectroscopy, spectroscopic ellipsometry, and field emission scanning electron microscope measurements the evaluation of plasmonic features and correlation of them with various metallic and metal-oxide nanoclusters inside the thin film and the heterojunction interface are carried out. Moreover, we have thoroughly analyzed the applicability of plasmon enhanced thin film as a backscattering layer based on (a) verification of plasmonic behavior in Ga-doped ZnO (GZO) film (~150 nm), (b) checking on the sustainability of such plasmonic behavior in ultrathin GZO (~5 nm) layer, (c) investigation of plasmonic feature at the heterojunction, (d) band offset studies at the plasmon-enhanced-GZO/CIGSe heterojunction, and (e) investigating the electrical performance of the junction to verify the linear behavior and resistivity calculation of the heterojunction.

Acknowledgments This work is partially supported by BRNS, DAE, (No. 37(3)/14/20/2014-BRNS) and DST CERI (DST/TM/CERI/C51(G)), DST-RFBR Project under India-Russia Programme of Cooperation in Science and Technology (No. DST/INT/RFBR/IDIR/P-17/2016). We are thankful to DIBS, FESEM, EDX, and XRD facility equipped at Sophisticated Instrument Centre (SIC) at IIT Indore. The authors Vivek Garg acknowledge UGC and, Brajendra S. Sengar and Amitesh Kumar acknowledge CSIR India for their fellowships. Prof. Shaibal Mukherjee is thankful to Ministry of Electronics and Information Technology (MeitY) Young Faculty Research Fellowship (YFRF) award under Visvesvaraya Ph.D. Scheme for Electronics and Information Technology and DST and IUSSTF for BASE Fellowship award. We are thankful to Dr. D. M. Phase, Dr. R. J. Chaudhary and Mr. A. Wadikar for using AIPES beam line Indus facility at RRCAT.

References [1] V. Garg, B. S. Sengar, A. Kumar, G. Siddharth, S. Kumar, and S. Mukherjee, Investigation of valence plasmon excitations in GMZO thin film and their suitability for plasmon-enhanced buffer-less solar cells, Solar Energy, vol. 178, pp. 114-124, January 15, 2019. [2] B. S. Sengar, V. Garg, A. Kumar, S. Kumar, and S. Mukherjee, Surface layer investigation of dual ion beam sputtered Cu2ZnSn(S,Se)4 thin film for open circuit voltage improvement, Journal of Physics D: Applied Physics, vol. 51, no. 31LT01, pp. 18, July 12, 2018.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-06: Band Offset Studies in Oxide Semiconductors Pratima Sen School of Physics, Devi Ahilya University, Khandwa road, Indore-452001, India; [email protected] Transparent semiconducting oxides play an important role in today’s optoelectronic devices such as laser diodes, light emitting diodes, photodetectors, logic gates, switches and memory elements. The transistors involved in making these devices comprise of the heterostructure interfaces. The potential barrier experienced by the charge carriers at these interfaces controls the performance of the transistors. Small barriers encountered in Si based transistors create the problem of large leakage current and warrants usage of alternative materials. At the energy band offset of two materials, the heterostructure interface forms the Band offset. Two types of band offsets, their monitoring by suitable impurity doping as well as their applications are discussed. Results of the band offset measurements in MgZnO/ZnO, NiZnO/ZnO as well as Cr2O3/TiCr2O3 using Indus -1, BL-2 beamline suggest that 9% Mg doping in ZnO gives rise to type I alignment at MgZnO/ZnO interface while 21% Mg doping in ZnO gives rise to type II band alignment. Both NiZnO/ZnO as well as Cr2O3/TiCr2O3 give type II band alignment.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-07: Mott-Hubbard type insulating nature of epitaxial LaVO3 thin films R. J. Choudhary, Anupam Jana and D. M. Phase UGC-DAE Consortium for Scientific Research, Indore 452001, Madhya Pradesh, India

In transition metal oxides, the ligand p and metal d hybridization plays a significant role to define their electronic properties. The substrate induced strain in a thin film caused by the lattice mismatching with a substrate would modify the hybridization and hence the electronic ground state. In the present study we attempt to modify the hybridization strength between O

2p and V 3d of LaVO3 via thin film form of LaVO3 and try to investigate the possible electronic state at room temperature. We deposited LaVO3 film on LaAlO3 substrate via pulsed laser deposition technique. The electronic structure of the epitaxial LaVO3 thin film has been studied using resonant photoemission spectroscopy (RPES) and x-ray absorption near edge spectroscopy (XANES) measurements. The RPES study confirms the mixing of V 3d with O 2p states and V 3d character at 6.9 eV and 1.5 eV binding energies respectively. The resonant behaviour of V 3d state at 1.5 eV binding energy suggests 3dn−1 final is attributed as a lower Hubbard band. The parameters (U and ∆) calculated from the combination of photoemission and absorption spectra suggests the Mott-Hubbard type insulating state of LaVO3 thin film at room temperature. The on-site d-d Coulomb repulsion energy (U) increases with the decrease of LaVO3 film thickness due to the reduction of dielectric screening in thinner samples. The spectroscopic observation suggests that the Mott-Hubbard type insulating nature of epitaxial

LaVO3 thin films at room temperature, different from its bulk counterpart, which is placed intermediate between the charge transfer and Mott-Hubbard regime.

References:

1. Anupam Jana, R. J. Choudhary and D. M. Phase, Phys. Rev. B 98, 075124 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-08: Study of metal nitride thin films by N K-edge absorption spectroscopy at BL-1, Indus 2

Mukul Gupta, D. M. Phase and Ajay Gupta 1 UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India 2Amity Center for Spintronic Materials, Amity University, Sector 125, Noida 201 303, India Email: [email protected] Indus beamline(s) Used: BL-1, BL-9 Indus-2 Metallic carbides, nitrides, oxides and fluorides are an important class of compounds. Soft x-ray absorption near edge spectroscopy (XANES) of C, N, O and F-edges is an excellent tool to probe the oxidation states, electronic spin configurations, ligand-field splitting, and crystal structures of such compounds. In addition, the complementary information obtained from the L-edge features of 3d, M- edge features of 4d, and in some cases N-edge features 5d transition metals (TM) can be combined in a unique way to obtained the fundamental electronic and structural properties [1]. In this talk, N K-edge features of early 3d TM nitrides (TMN) viz. TiN will be compared with a late TMN compound i.e. FeN. Although N K-edge features of early TMN viz. TiN, CrN are well- established, they have been used for the first time in FeN to identify the local structure [2]. In addition, Fe K-edge features were also studied [2]. Fig. 1 compares the N K-edge XANES of a FeN and TiN thin film. The N K-edge features in these compounds differs as (i) the energy separation between first two features is larger (ii) the intensity of second feature (eg in TiN and t2g in FeN) is much less pronounced in FeN. These difference can be understood as FeN crystalizes in a Zinc Blende (ZB) type opposed to the Rock Salt (RS) type structure in TiN. The coordination between metal and N atoms is octahedral in a RS as opposed to tetrahedral in a ZB-type structure.

t e 2g g

TiN

4sp+2p

(arb. units) (arb. FeN

 e g t 2g

390 405 420 435 Photon Energy (eV)

Fig. 1: N K-edge XANES measurements taken at soft x-ray absorption spectroscopy (SXAS) beamline at BL- 01, Indus-2 synchrotron radiation source for a for TiN and FeN thin film grown by reactive sputtering (left). The t2g and eg state of Ti and Fe in +3 states are schematically shown for TiN and FeN (right).

The N K-edge XANES has also been studied to understand the thickness dependent structural transition in FeN by doing in-situ as well as ex-situ measurements [3]. These results will be discussed in this talk. The feasibility of N K-edge has attracted users to probe N K-edge XANES in GaN, CrN, TiN, ScN, NbN, Ag(N), Pt(N) N-doped graphene etc. Akhil Tayal, Nidhi Pandey and Niti are acknowledged for their contribution in this work. Technical help provided by L. Behera in sample preparation and R. Sah in XAS measurements is gratefully acknowledged. References

[1] J.G. Chen, Surface Science Reports 30, 1, 152 (1997). [2] A. Tayal, M. Gupta, A. Gupta, P. Rajput, J. Stahn, Phys. Rev. B 92, 054109 (2015). [3] M. Gupta et al, http://arxiv.org/abs/1902.03388v1 (2019). 11

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-09: Extended x-ray absorption fine structure spectroscopy and x-ray absorption near edge spectroscopy study of aliovalent co-doped ceria to correlate local structural changes with oxygen vacancies clustering S. C. Shirbhate1, A. K. Yadav2, and S. A. Acharya1

1Department of Physics, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440033, India

2Atomic and molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India Email: [email protected]

The present work is intended to provide key insight of extrinsic and intrinsic oxygen vacancy clustering, dissociation mechanism and their influence on Oxy-ion conductivity in co-doped ceria system. Co-dopants induced atomic-scale changes in ceria are probed by extended X-ray absorption fine structure spectroscopy, X-ray absorption near edge spectra, and Raman spectroscopy. The results are explored to establish a correlation between atomic level structural changes (coordination number, interatomic spacing)  formation of dimer and trimer type cation-oxygen vacancies defect complex (intrinsic and extrinsic)  dissociation of oxygen vacancies from defect cluster  ionic conductivity temperature. It is a strategic approach to understand key physics of ionic conductivity mechanism in order to reduce operating temperature of electrolytes for intermediate temperature (300–450 C) electrochemical devices for the first time.

Acknowledgment: S.A.A. acknowledges NRB-DRDO for financial funding: NRB-356/MAT/14-15 and UGC- CSR-DAE, Indore, for partial fundingfor collaborative research at RRCAT, Indore CSR-IC- BL-43/CRS-140-2014-15 and special thanks to Dr. S. N. Jha

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-10: Optical and X-ray Absorption Spectroscopy Studies on Band gap Opened Graphene Solid Sheets Ganapathi Bharathi1, Devaraj Nataraj1, Mukul Gupta2, Deodatta Phase2, Nirmalendu Patra3, Shambhu Nath Jha3 and Dibyendu Bhattacharyya3 1Quantum Materials & Device Lab and UGC-Centre with Potential for Excellence for the Advanced Studies in Physics for Development of Solar Energy Materials and Devices, Department of Physics, Bharathiar University, Coimatore-641046, TN, India. 2UGC-DAE Consortium for Scientific Research, Indore, India.3Atomic & Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai, India.

Presenting Author/Corresponding Author Email:[email protected] (Prof. Dr. Devaraj NATARAJ) Here, we prepared micron sized solid sheets made up of graphene quantum dots, which is single crystalline in structure. We found that the as prepared solid sheet has energy band gap to absorb light energy in the visible region.1 Hence therefore it was possible to produce high magnitude photocurrent from the as obtained larger sized graphene solid sheet samples for the first time. Since graphene in its pristine form has no energy band gap, its application in the optoelectronic device fabrication as active layer is not possible. Since we have induced energy band gap in the graphene solid sheets, it was possible to use this material as an active layer in the device fabrication. We made this graphene solid sheet through metal atom mediated growth process. Metal atom(s) has interconnected the nano sized graphene quantum dots in a perfect way so that larger sized single crystalline form quantum nanostructure was made possible. Since the interconnecting metal atoms are harder to see through even through powerful electron and other microscopes, we employed the X-ray absorption characterization to confirm the presence and role of metallic atoms in the graphene solid sheet. The present paper will discuss the experimental work elaborately.

Figure1. HRTEM images of single crystalline solid sheets

Acknowledgements:

Author DN thanks UGC for sanctioning CPEPA centre for Advanced studies in physics for the Development of Solar Energy Materials and Devices (Award No. F. No. 2-1/2013(NS/PE)). Author DN also acknowledges Department of Science and Technology, Govt. of India, for the research funding under DST-SERI scheme (Award No. DST/TM/SERI/FR/232/G).

References:-

[1] Ganapathi Bharathi, Devaraj Nataraj et al. Scientific Reports 7 (2017) 10850 13

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-11: Facility for X-ray imaging & micro-CT at imaging beamline Indus-2

A.K. Agrawal1, Balwant Singh1, Payal Singhai1, Y.S. Kashyap1, Mayank Shukla1 1Technical Physics Division, Bhabha Atomic Research Centre, Mumbai, India, 400085 Email: [email protected] Indus beamline: Used: BL-4 Imaging beamline Indus-2 X-ray imaging has undergone revolutionary improvements with the introduction of synchrotron sources and advance detector technologies, opening new possibilities for research in material and bio-medical application. The synchrotron source characteristics - high brilliance, high coherence, and possibility of monochromatization has opened new horizons in imaging science such as phase contrast imaging, diffraction enhanced imaging, real-time imaging of transient phenomena, and in-situ 3D imaging. High spatial and energy resolution not only enable new modes, but also allows conventional imaging techniques such as tomography to be carried out approaching micrometer resolution. X-ray phase contrast imaging has opened the possibility to distinguish features with very small density difference. Therefore this technique is very useful in bio-medical research on animals and plants. Synchrotron based micro-imaging has also shown promising results in the studies of advanced materials such as polymers, composites, ceramics, bio and geo-materials. The possibility to use high intensity monochromatic beam also allows element specific imaging using multi-energy imaging, K edge subtraction imaging. With availability of Indus-2 synchrotron source at RRCAT, Indore, we have designed, developed and installed an advanced imaging facility to carry out absorption and phase sensitive imaging and micro-tomography for material and medical science application. The beam-line has both monochromatic as well as white beam mode of operation. In monochromatic mode, the energy range covered is 8-35 keV while in white beam mode energy up-to 50kev is available. The maximum beam-dimension in the experimental station is 100 mm X 10 mm and photon flux is ~1010ph/s in monochromatic mode while it is 1016 ph/s in white-beam mode. Several detectors such as CCD, flat panel and X-ray microscope with sub-micron resolution along with precision sample manipulators have been installed. Techniques such as radiography, propagation and analyzer based phase imaging, 3D tomography in absorption and phase contrast mode; real-time imaging etc. have already been implemented. This national facility is being used by several researchers across the country for advanced applications in bio-medical science research, characterization of advanced materials and several new challenging applications.

Fig-1 Illustrative example of 3D X-ray tomography images of Human bone and polyurethane foam References

[1] A. K. Agrawal, B. Singh, Y.S. Kashyap, M. Shukla, P. S. Sarkar, A. Sinha; J. Synchrotron Rad. 22, (2015) 1531–1539.

[2] Harsha Praneeth Pavani, T. P. Tezeswi, Ashish Kumar Agrawal: Advances in Cement Research 01/2019;DOI:10.1680/jadcr.18.00066 14

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-12: X-RAY LIGA FACILITY AT INDUS-2 SYNCHROTRON RADIATION SOURCE Pushpen Mondal RRCAT, Indore

Abstract: The synchrotron radiation based x-ray lithography activities being carried out at Indus-2 synchrotron radiation source located at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore. X-ray lithography is suitable and versatile technique to fabricate high aspect ratio and high spatial resolution micro/nano structures. X-ray lithography facility is operational on Indus-2 and is a national facility for microfabrication research. The facility provides wide lithographic window using x- ray energies from 1-40 keV and an exposure area of sizes upto ~100 mm x 100mm. X-ray exposures can be carried out in air, vacuum and He gas environment. This talk gives brief details on x-ray lithography, x-ray LIGA (LIGA is German acronym for Lithography, Galvanoformung (electrodeposition) and Abformung (molding)), description of x-ray lithography beamline facility and complimentary processing techniques required for realization of microstructures. Various high aspect ratio structures fabricated at Indus-2 x-ray LIGA facility, these are microfluidic device prototyping with a variety of materials such as PMMA, SU8 and PDMS, mold/ master fabrication for rapid and smooth scale-up for mass manufacturing, MEMS & other related high aspect ratio structure.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-13: SWAXS beamline at Indus-2

D.Sen1, Jitendra Bahadur1, Avik Das1 1Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai-400085, India Email: [email protected] Small-angle scattering [1,2] is an important non-destructive technique that provides quantitative structural information about the inhomogeneities i.e., the density fluctuations in materials [3,5], over a length-scale ranging from typically one nanometer to one hundred of nanometer. Such mesoscopic inhomogeneities, that govern various physicochemical properties of materials, are ubiquitous in the purview of condensed matter. These include precipitates, nano-structures, membranes, colloids, polymers, micelles, pores etc. In a unique way, this nondestructive technique opens the door of “nanocosmos” and allows quantitative analysis in a statistically averaged fashion and thus has become indispensable for every domain of science and technology. A Small and wide angle X-ray scattering beamline (BL-18) has been developed at Indus- 2, synchrotron source, RRCAT. The beamline is now operational and is under trial operation. This beamline will be utilized to probe mesoscopic structure in technologically relevant materials covering the field of ceramics, alloys, biology, colloids, soft-matter etc. SAXS measurements on a few samples have been carried out during trial operation. At this moment, the beamline uses a 1D position sensitive detector for collection of scattering data within q range of ~0.25 nm-1 to 6 nm-1. Soon, a 2D online image plate is going to be put with variable sample to detector distance which will allow more efficient data collection over a wide q range. In this talk, we will discuss about the development of BL-18 and present a first few set of data those have been collected during the trial operation, after giving an introduction to this novel technique. We would like to like to thank Dr. S. Mazumder (deceased), SSPD, BARC who initiated the development of the beamline. We would also like to thank Dr. S. M. Yusuf, Head, SSPD, BARC for his kind support.

References

[1] O. Glatter and O. Kratky; Small-Angle X-ray Scattering (Academic press, London, 1982)

[2] A. Guinier and G. Fournet; Small-Angle Scattering of X-rays (Wiley, New York 1955)

[3] Priyanka Biswas, D. Sen, S. Mazumder, C.B. Basak, P. Doshi Langmuir (2016) 32 2464-2473

[4] Ayan Maity, Avik Das, Debasis Sen, S. Mazumder, Vivek Polshettiwar, Langmuir 33, 13774–13782 (2017)

[5] D. Sen, J. Bahadur, S. Mazumder, G. Santoro, S. Yu and S. V. Roth Soft Matter 10 (2014) 1621-1627

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-14: EXTREME CONDITIONS ANGLE DISPERSIVE / ENERGY DISPERSIVE X-RAY DIFFRACTION (ECXRD) BEAMLINE (BL-11): BEAMLINE DETAILS AND RESENT RESULTS.

Velaga Srihari High Pressure & Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India. Email: [email protected] Extreme conditions x-ray diffraction (ECXRD) beamline has been developed at bending magnet port BL-11 of Indus-2 Synchrotron source. This beamline has the provision to carry out two variants of x-ray diffraction viz. angle dispersive x-ray diffraction (ADXRD) and energy dispersive x-ray diffraction (EDXRD) [10]. In angle dispersive method, the monochromatic x-ray beam is incident on sample and the diffraction pattern is recorded as a function of angle () whereas in case of energy dispersive method, the sample is exposed to the white x-ray beam and the diffracted x-rays are energy analysed at a fixed angle. Both the techniques have their own merits. EDXRD technique is advantageous in case of constrained geometries and depth resolved investigations whereas ADXRD provides high resolution diffraction data for detailed structural refinement. HPGe detector integrated with 2-circle goniometer will be used for the EDXRD technique. For ADXRD measurements, white SR beam from bending magnet is monochromatized using Si (111) channel cut monochromator, which provides energy tenability from 8 keV to 30 keV and the 2D diffraction image is collected at MAR345 image plate detector. an elliptically bendable Kirkpatrick Baez (KB) mirror system has been installed to focus hard x-rays at the sample position. The experimental facilities at this beamline are optimized for structural investigations of materials under static compression employing DAC, high temperature along with static compression, powder diffraction, high temperature powder diffraction, grazing incidence x-ray diffraction (GIXRD) and scope for the customized user experiments. With the availability of a STOE make high temperature furnace, it can also be used for performing high temperature measurements up to 1500 K. Besides high pressure/ high temperature investigations, this beamline can also be used for grazing incidence x-ray diffraction measurements. The 2D detector available at the ADXRD station provides both in- plane and out-plane diffraction in one acquisition which can be analysed to deduce vital information about texturing and residual compressive or tensile strains in the thin films. References

[1] K. K. Pandey, H. K. Poswal, A. K. Mishra, Abhilash Dwivedi, R. Vasanthi, Nandini Garg andSurinder M.Sharma, Pramana – Journal of Physics, 80 (2013)607.

[2] Physics News, Bulletin of the Indian Physics association 48 (2018) 48.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-15: Some recent results using HXPES beamline, Indus-2

U. K. Goutam1, 2, J. Singh1, 2, R. K. Sharma1, 2, Jagannath1 1Technical Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India 2BARC Beamline Section, Raja Ramanna Centre for Advanced Technology, Indore 452013, India Email: [email protected] Indus Beamline: Photo-Electron Spectroscopy (PES-BL-14) The Hard X-ray Photo-Electron Spectroscopy (HXPES) beamline PES-BL14, installed at the bending magnet port at Indus-2, can be used for photo-emission electron spectroscopy measurements on solid samples. In this talk, a brief about the beamline, other facilities and some recent scientific results are described. The PES-BL14 has a working energy range of 3– 15 keV for significantly increased sensitivity (information depth more than 10 nm) which can provide information (in a non-destructive way) on bulk electronic structure or on chemical composition of deeply buried interfaces. The beamline is equipped with an in-house developed double-crystal monochromator [Si (111)] and a high energy (up to 15 keV) high resolution (meV) hemispherical analyzer with MCP and CCD detector system. Ever since the commissioning of the beamline several users (>100) from different institutes have used the beamline. In one experiment from the beamline, different types of Carbon atoms present in the Magnesium phthalocyanine (MgPc) molecule in different bonding environments using high- resolution HXPES measurements were resolved. For this purpose, 20 nm thin films of MgPc were thermally evaporated on silicon substrates. These thin films were annealed in air at 300°C and 350°C for 1 h. The high-resolution HAXPES spectra of the annealed and room-temperature (27°C) films were recorded at a pass energy of 20 eV with a step size of 0.05 eV.

Recently, in another experiment, B4C/W multilayer structures were studied using HXPES beamline. Different B4C layer thicknesses (1.3, 1.9, 2.8 and 4.0nm) were deposited on W (2.7nm). HXPES measurements carried out at excitation energy of 4404eV with mean free path to be between 4.2 to 6.3nm depending on the element and core level. The HXPES results suggest that most of the boron is in the chemical state of B4C in the multilayer structures with small contribution of B2O3. Also as the B4C layer thickness increases, B content increases with a decrease of W content. W is still visible at 4.0 nm thickness of B4C top layer as the escape depth is high at 4404eV. In another experiment, NCH electrode material was studied using HXPES. The high resolution C1s and O1s spectra reveal the presence of carbonate species and hydroxyl units. The Ni 2p spectrum is fitted with shake-up satellite peaks, represented the Ni2+ state. Also the peak splitting energy was 17.7 eV between it Ni 2p3/2 and Ni 2p1/2. The XPS results confirmed the 2- - presence of CO3 and OH groups, thus affirming the formation of NCH phase.

References 1. Jagannath, U K Goutam, R K Sharma, J Singh, K Dutta, U S Sule, Pradeep R, and S C Gadkari. J. Synchrotron Rad. (2018) 25, 1541–1547. 2. Rao, P. N., Goutam, U. K., Kumar, P., Gupta, M., Ganguli, T. & Rai, S.K. (2019). J. Synchrotron Rad. 26, https://doi.org/10.1107/S1600577519002339. 3. Prateek Bhojane, Lichchhavi Sinha, Uttam K. Goutam and Parasharam M. Shirage; Electrochimica Acta 296 (2019) 112-119.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-16: XAFS study of metal complexes using beamlines BL-8 and BL-9 at Indus -2 B.D. Shrivastava School of Studies in Physics, Vikram University, Ujjain (M.P.) -456010 Email: [email protected]

Indus-2 beamline used: Scanning EXAFS BL-8 and BL-9

We have been using Indus-2 EXAFS beamlines BL-8 and BL-9 for the last 10 years. In the present talk, I would like to discuss four of the studies done by us on the metal complexes using the above mentioned beamlines. In one study, four copper complexes with 2,2'-bipyridine and 1,10-phenanthroline have been studied using EXAFS. Two of the complexes are monohydroxo-bridged and two are dihydroxo-bridged. For two of the complexes, the crystallographic data are not available and hence, we have determined their structural parameters by fitting their experimental EXAFS data with the same theoretical models which were generated for the other two complexes which are analogous complexes of the other two. On the basis of analysis of the EXAFS data, these four complexes have been shown to be binuclear, i.e., they contain two metal atoms per cluster having copper in +2 oxidation state, a result which can be obtained only with EXAFS spectroscopy. The coordination geometry about the copper (II) ions in these complexes have been depicted. In another study, the technique of XAFS has been applied for the identification of various coordination geometries present in tetraaquabis(isonicotinato) metal(II) complexes M(NC5H4-p-CO2)2.4(H2O) with M= Mn, Fe, Co, Ni, Cu, Zn. Using a simple cluster of atoms around metal ions obtained from EXAFS analysis, ab-initio XANES simulations have been performed for almost similar coordination around different metals in these complexes. Specific features observed in the experimental as well as calculated XANES spectra have been correlated to the variation in p-density of states (DOS). As compared to other metal complexes, Cu complex was found to be highly distorted from octahedral structure. It has been shown that the shoulder feature obtained in the main edge region of Cu complex is due to the splitting of p-DOS in the presence of highly distorted octahedral field. In another study XAFS at the Ni K-edge of the four nickel (II) complexes with distorted geometry have been investigated. The complexes are mononuclear and have Schiff base and have stoichiometry M(L)(B), where L is N-[(1)-pyridin-2-ylmethylidene]benzohydrazide and B is diethylenetriamine /2,2′-bipyridine. From EXAFS analysis, the octahedral coordination around metal ions has been confirmed. Theoretical XANES spectra generated for Ni coordination present in these complexes show features whose shape and intensity depends on corresponding metals p- and s-DOS. Hence, by using theoretical XANES spectra, distortion in octahedral structure of Ni complexes has been studied. In yet another study, the coordination geometry around the Cu atom in two copper(II) mixed ligand complexes with pyridinedicarboxylic acid as one of the ligands, have been investigated by XAFS. The weak pre-edge features arise from bound state transitions. Although the 1s→3d transition is forbidden by dipole selection rules, it is nevertheless observed due to 3d+4p mixing as well as due to quadrupole transition. The same intensity of weak feature in the pre-edge region and similar edge features of both complexes shows that the geometry around the copper metal ion in both complexes is the same, i.e., square pyramidal. Recently, we have been carrying out studies on methods of speciation using mixtures of Fe(II) and Fe(III) compounds.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-17: X-ray study of interfaces in magnetic thin fims and multilayers Ajay Gupta Amity Center for Spintronic Materials, Amity University UP, Noida 201313 [email protected]

Magnetic thin films and multilayers are an important class of nanostructures which exhibit a variety of interesting phenomena like giant magnetoresistance, tunnel magnetoresistance, exchange bias, spin-orbit torque etc., and are at the heart of a number of spintronic devices. Interfaces play a significant role in determining the functional properties of magnetic multilayers. For example, perpendicular magnetic anisotropy in thin films is believed to have its origin in interfacial hybridization and anisotropy of bonds; in magnetic tunnel junctions even a monolayer of impurity or transition-metal oxide can drastically deteriorate the magnetoresistance. Therefore, it is important to elucidate both atomic and electronic structure of interfacial region in multilayers in order to understand their novel properties as well as to tailor the same through tailoring the interfaces. Interfacial region of interest may vary from a fraction of a nm to a few nm only, and therefore, experimental techniques needed to probe it, should have sensitivity and depth- selectivity which matches with this requirement. An overview of various strategies being used by us to selectively probe the interfaces will be presented. Experimental techniques being used include soft x-ray absorption spectroscopy and x-ray magnetic circular dichroism (BL-01), soft x-ray reflectivity (BL-03), XAFS (BL-09), anomalous x-ray reflectivity (BL-16), wide angle diffraction (BL-11, BL-12), small angle x-ray scattering (PETRA III), nuclear resonance scattering (PETRA III), hard x-ray photoemission (PETRA III). Depth selectivity is achieved either using x-ray standing waves or by doing in-situ measurements during the evolution of interfaces. Specific results obtained on systems like Fe/MgO, Fe/W, CoFeB/MgO, Ta/Co2FeAl/MgO will be presented.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-18: Electronic Structure Modifications in doped ZnO and RFeO3 Systems

D.G.Kuberkar Department of Nanoscience & Advanced Materials, Saurashtra University, Rajkot-05, India Email: [email protected] Indus beamline(s) Used: INDUS – 1, BL-02 and INDUS – 2, BL-01 Diluted Magnetic Semiconductors are suitable for new functional devices used in the memory and switching applications. Studies on Transition Metal-doped ZnO having TC >RT have opened a new research direction in this field owing to the tunable band gap and electronic structure. Studies on the origin of ferromagnetism in magnetic and non- magnetic ion-doped ZnO have resulted in the interesting results and is a topic of debate due to the diversity of the properties and underlying mechanisms. Multiferroics are unique class of materials exhibiting, simultaneously, ferroelectric ferromagnetic properties in the same phase. Amongst various multiferroics, BiFeO3 (BFO) is well studied owing to the ferroelectric (TC) and ferromagnetic (TN) transitions, well above RT. However, in BFO, the presence of high leakage current, small remanent polarization and inhomogeneous spin structure restrict its usefulness in device application. Various remedies have been suggested, such as, application of high magnetic field, chemical doping and variation in structural strain, to overcome these shortcomings. In this talk, I will summarize, our results on the studies on the modifications in the electronic structure of Co, Fe and Fe-Al co-doped ZnO systems, which have been understood in the light of creation of oxygen vacancies and local ordering of Fe – ions in ZnO host matrix leading to the enhancement in ferromagnetic exchange interaction. In addition, Strain-induced modifications in the structure, electronic structure, electrical, and ferroelectric properties of the Bi0.90Ca0.10FeO3 (BCFO)/Nb-doped SrTiO3 (100) films will be discussed in light of variation in film thickness. Improvement in the bipolar resistive switching behavior with a decrement in oxygen vacancies and improvement in ferroelectric properties with increasing film thickness suggest the crucial role of oxygen vacancies and strain in modifying the electrical properties of the BCFO films. Improvement in the ferroelectric behavior is attributed to the increment in the Fe 3d-O 2p hybridization, localization of Fe 3deg/Bi 6s-O 2p orbitals, and reduction in the oxygen vacancies with an increase in the film thickness.

Colossal dielectric (CD) response is one of the unusual properties shown by RFeO3 (R = La, Pr and Sm). The results of the studies on crystal structure, electronic structure and dielectric properties of Er1-xLaxFeO3 (ELFO) (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) orthoferrites will be presented. Effect of grain and grain boundary contribution on the dielectric behavior is studied using complex dielectric permittivity. The results of the investigations on the electronic structure modifications in ELFO using Soft X-ray Absorption Spectroscopy (SXAS) will be discussed in the light of observed CD behaviour.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-19: X-ray investigations of doped-diamond and strongly correlated iridate systems

Dinesh Kumar, Sreya Suresh, T.S. Suraj, Dhruba Das, V. Praveen Bhallamudi, and M. S. Ramachandra Rao Department of Physics, Nano Functional Materials Technology Center and Materials Science Research Center, Indian Institute of Technology Madras, Chennai 600036, India. Corresponding Author’s Email: [email protected]

Indus beamline(s) Used: BL-1

Correlated material systems exhibit a plethora of exotic properties from superconductivity to existence of topological phases due to coulomb correlations and its interplay between spin orbit coupling. In this talk I will discuss two examples of our work in understanding correlated material phenomena. The first example deals with superconductivity in diamond. Boron doping in diamond above a critical concentration results in superconductivity [1]. We have used X-ray absorption (XAS) [2,3] at INDUS to probe the B 2p, C 2p density of states (DOS) and also the formation of the impurity band which ultimately leads to superconductivity. Direct probe of the impurity band using XAS show a systematic increase in the absorption intensity of the bandgap states. A large band gap and a relatively large acceptor binding energy of a simple acceptor boron creates a well isolated impurity Hubbard bands and mid-gap bands visible in XAS. We are currently investigating n-type doping in diamond, which is more challenging than p-type doping with Boron, and is an area of active research for electronic applications of diamond. There also are theoretical reports of possible room-temperature superconductivity in Nitrogen-doped diamond [4]. Also, nitrogen- doped diamond is useful from quantum sensing and computing application as well. X-ray based investigation in case of n-type doping in diamond has not yet been done. We propose to study the evolution of DOS with increasing doping level of nitrogen and phosphorus in diamond. We propose to use both XAS and XES to probe the unoccupied and occupied DOS respectively. In the second example we will look at strongly correlated Iridate oxide systems. Here the spin-orbit coupling energy is comparable to coulomb interactions and bandgaps [5]. Pyrochlore iridates, R2Ir2O7 (where R is a lanthanoid or yttrium), are particularly interesting where several correlated electron physics have been observed, such as novel topological phases [6], geometrically frustrated magnetism and zero field quantum criticality [7]. In bulk single crystals the properties can be tuned by doping which alters the Ir-O-Ir bond angle [8]. In case of thin films, strain-tuning via substrate can induce change in bond angles and is reflected in transport and magnetic behavior [9]. Synchrotron experiments like XMCD and XAS will provide information regarding the internal electronic and magnetic structure. We propose a collaborative effort to use synchrotron-based spectroscopy to investigate Iridate thin films and correlate to their properties.

References [1] Ekimov, E. A., et al, Nature 428.6982 (2004): 542. [2] Kumar, Dinesh, .. and Rao et al., Applied Surface Science 466 (2019): 498-502. [3] Kumar, Dinesh,… and Rao et al., Physica C: Superconductivity and its Applications 555 (2018): 28-34. [4] Baskaran, G, Science and Technology of Advanced Materials 7.S1 (2006): S49. [5] Kondo, Takeshi, M. Nakayama, R. Chen, J. J. Ishikawa, E-G. Moon, T. Yamamoto, Y. Ota et al, Nature communications 6 (2015): 10042. [6] Tokiwa, Y., Ishikawa, J. J., Nakatsuji, S. & Gegenwart, P. Quantum criticality in a metallic spin liquid. Nat. Mater. 13, 356–359 (2014).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

[7] Udagawa, M., & Moessner, R. (2013). Anomalous Hall Effect from Frustration-Tuned Scalar Chirality Distribution in Pr 2 Ir 2 O 7. Physical review letters, 111(3), 036602. [8] Koo, H. J., Whangbo, M. H., & Kennedy, B. J. (1998). Similarities and Differences in the Structural and Electronic Properties of Ruthenium and Iridium Pyrochlores A2M2O7− y (M= Ru, Ir). Journal of Solid State Chemistry, 136(2), 269-273. [9] Ohtsuki, Takumi, et al. "Spontaneous Hall effect induced by strain in Pr2Ir2O7 epitaxial thin films." arXiv preprint arXiv:1711.07813 (2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-20: Role of Valence Plasmons in Interaction of Synchrotron Radiation with Materials

Shailendra Kumar UGC DAE Consortium for Scientific Research, Indore email: [email protected]

Propagation of excited electrons triggers excitation of free and valence electrons plasmons in metals, semiconductor and insulator materials. These plasmons play role in all experiments, done using synchrotron source. In this talk, the role valence electron plasmons in photoelectron spectroscopy, transmission and reflection spectra and thermal wave spectroscopy will be presented. These experiments were performed using Indus 1 and 2 synchrotron sources. Study of valence plasmons in semiconductors and oxide materials is helpful in new designs of optoelectronic and photovoltaic devices.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-21: Enhanced Ferromagnetism by Ion Irradiation for Substitutionally Cobalt Doped ZnO Films S.K.Neogi1, Md. A. Ahmed2, A. Banerjee2,3, S. Bandyopadhyay2,3* 1 Department of Physics, Adamas University, Barasat, Barrackpore Road, Jagannathpur, Kolkata 700126, India 2Department of Physics, University of Calcutta, 92 APC Road, Kolkata:700009, India 3CRNN, University of Calcutta, JB Block, Sector III, Salt Lake, Kolkata: 700098, India Presenting Author’s Email:[email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: EXAFS (BL-8)

Despite many fascinating aspects the primary problem in Dilute Magnetic Semiconductor with ZnO as host is contamination of dopant element or its simple or complex forms of oxides. And the question naturally comes that developed ferromagnetism may not be the intrinsic property rather arising from the contaminated secondary phase. Above a certain limit the transition metal (TM) dopants can’t substitutionally replace Zn ions and rather occupy interstitial position and when many TM dopants are positioned interstitially they may segregate to form secondary phase. Hence careful scrutiny is essential to check the nature of TM dopants occupation in the host ZnO matrix. In this context a thorough local structure study (X-ray Absorption spectroscopy [XAS]) has been made for Co doped ZnO films. Synchrotron based XAS data were interpreted using X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure spectroscopy (EXAFS) measurements. 3 at% Co doped sol-gel derived films were irradiated with 800 keV Ar ion beam. The studied films were un-irradiated and irradiated with fluences 5 x 1014, 2.5 x 1015 and 1016 ions/cm2. Apart from XAS study the films were characterized structurally (X-ray diffraction [XRD]), morphologically (Field Induced Scanning Electron Microscopy), optically (UV- visible, Raman spectroscopy and Photoluminescence [PL] measurements), magnetically (field and temperature dependent magnetization measurements). XRD patterns show single-phase wurtzite structure of the films and indicate presence of defects. Raman spectra confirm single- phase structure of the films and indicate slight structural degradation in highest fluence irradiated film. The high substitutional incorporation of Co2+ at Zn2+ site was demonstrated from UV-visible spectra by d-d transition. The analysis of XANES and EXAFS spectra strongly reconfirms further the proper substitutional incorporation of Co2+ at Zn2+ site. All films are intrinsically ferromagnetic. The substantial enhancement of ferromagnetism (2.5 fold) has been observed upon irradiation (highest fluence) and it has been interpreted in terms of defects as evidenced from PL measurement. Hence the effect of Ar ion beam irradiation is highly enhanced ferromagnetism and proper Co substituted ZnO film.

We acknowledge IUAC, New Delhi, India for ion beam irradiation and RRCAT, Indore, India for XAS measurements utilizing their dispersive EXAFS beam line (BL 8) of INDUS 2 Synchrotron Source (2.0 GeV, 100 mA). We sincerely thank Dr. S. N. Jha of RRCAT for his kind assistance in the XAS measurement. We thank DST, India for financial support and SINP, Kolkata and JNCASR Bangalore for facilitating the powder XRD experiments at the Indian Beamline (BL-18B), Photon Factory, KEK, Japan.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-22: Investigation of Mn 3d derived states in La0.2Sr0.8MnO3 Priyamedha Sharma1, R.J.Chaudhary2, D.M. Phase2 and R Bindu1. 1School of Basic Sciences, Indian Institute of Technology Mandi, Kamand, Himachal Pradesh- 175005, India 2UGC DAE Consortium for Scientific Research, University Campus, Khandwa Road,Indore-452017, India Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected]

Indus beamline(s) Used: AIPES beamline

We investigate the Mn 3d derived states in La0.2Sr0.8MnO3 to understand the temperature dependent spectral weight transfer observed in the valence band spectra. Towards this, we have used DFT and DFT+U calculations and x-ray and Mn 3p to 3d resonant photoemission spectroscopic techniques. Our results show that the calculation gives better representation of the experimental valence band spectra for on site Coulomb interaction energy U= 5eV. The room temperature resonant photoemission technique reveal that the valence band feature ~ 2 eV is of mainly 3dnL character (L is the ligand hole formed by ligand to metal charge transfer) and the feature ~ 5 eV is predominantly of O 2p character. As the sample enters the low temperature tetragonal and insulating phase, the Mn 3d character of feature ~2 eV increases and of feature ~ 5 eV, it decreases.

Acknowledgement: The authors thank Mr. A. Wadiker and Mr. Sharad Verma for extensive technical support during temperature dependent PES measurement at AIPES beamline, Indus-1 synchrotron source. R. Bindu and Priyamedha Sharma would like to thank UGC-DAE, CSR, Indore for financial support.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-23: Swift Heavy Ion Induced Phase Transition Studies in Oxide Semiconductors

Subodh K. Gautam1, Arkaprava Das1 Mukesh Rawat2, D.K. Shukla3, Parasmani Rajput4, A. Chettah5, D.M. Phase3, R.C. Ramola2 and Fouran Singh1 1Materials Science Group, Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi – 110 067, India. 2Department of Physics, Badshahi Thaul Campus, H.N.B.Garhwal University, Tehri Garhwal 249199, India. 3UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452017, India. 4Atomic & Molecular Physics Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085, India. 5LGMM Laboratory, Université 20 Août 1955-Skikda, BP 26, 21000 Skikda, Algeria. Presenting and Corresponding Author’s Email: [email protected], [email protected] Indus-2 beamline(s) Used: BL-01 & BL-09

Study of metal oxides and their nanostructures in family of functional oxides have great potential for the research due to a variety of applications such as transparent conducting window materials for solar cells, electron injecting materials in hybrid and dye sensitized solar cells, chemical sensors, catalysis, water splitting for hydrogen storage, nanomedicines etc. Particularly, titanium dioxide, zirconium oxides and cadmium oxides have wide interest in fundamental understanding of phase transition and response of their physio-chemical properties due to changes in the crystallite size, the nature of defects and stoichiometry. A detailed study of amorphous-nanocrystalline-anatase-rutile phase transition in TiO2 including reversible phase transformation [1-4], monoclinic-tetragonal-cubic phase transition in ZrO2 [5] and phenomenon of charge neutrality and its correlation with p-d hybridization [6-7] will be discussed. Softening and stiffening of phonons will also be presented along with its electronic structure as investigated using micro-Raman and/or near edge x-ray absorption fine structure studies.

References: [1]. Subodh K. Gautam and Fouran Singh et al, J. Appl. Phys. 115, 43504 (2014). [2]. Subodh K .Gautam and Fouran Singh et al, Acta Materialia 146, 253 (2018). [3]. Subodh K. Gautam and Fouran Singh et al, AIP Advances 5, 127212 (2015). [4]. Subodh K. Gautam and Fouran Singh et al, Phys. Chem. Chem. Phys. 18, 3618 (2016). [5]. M. Rawat and Fouran Singh et al, RSC Advances 6, 104425 (2016). [6]. Arkaprava Das and Fouran Singh et al, Scientific Reports 7, 40843 (2017). [7]. Arkaprava Das and Fouran Singh et al, Mater. Res. Express 4, 045901 (2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-24: XANES spectroscopy for characterization of ion conducting polymers

M. Dinachandra Singh1, Anshuman Dalvi2* and D. M. Phase3

1Department of Physics, BITS Pilani-Pilani Campus (RJ-333031), India

2 UGC-DAE Consortium for Scientific Research, Indore 452001, India * [email protected] It has been recently observed [1, 2] that PEO-LiCF3SO3 solid polymer electrolyte (SPE) exhibits a significant conductivity enhancement (~ 2 orders of magnitude) on dispersion of fine + crystallites of LATP i.e. Li Al0.3Ti1.7(PO4)3, a Li ion NASICON framework compound. For SPEs with low salt content (5 wt%) such a high value of ionic conductivity (~ 10-4 -1cm-1) at room temperature is encouraging. However, mechanism of ion transport, particularly contribution of NASICON grains, needs more understanding prior to application to energy devices. In our recent studies, XANES spectroscopy has been found to be particularly useful for conductivity-structure correlation and predicting ion pathways in the NASICON-polymer composites. The hybrid polymer-NASICON composite samples have been prepared in a wide range of compositions, viz. 5 LiCF3SO3-95[PEO1-x (LATP)x], for x = 0-0.7 (abbreviated as 0- 70LATP). The K-edge energies of carbon and ether oxygen (of PEO chains) were obtained for all of these compositions and analyzed. Most importantly, with increase in LATP content, the K-edge energy of ether oxygen (corresponds to 1s → σ* transition) gradually shifts towards higher value that in turn suggests Li+ ion crowding in polymer. Thus it is proposed that for low LATP content the Li+ ions prefer to stay in the polymer and conductivity is dominated by ionic motion in polymer phase. On further increasing LATP content, the K-edge energy value attains a maximum and subsequently shows a decreasing trend particularly for very high salt content (above x = 0.6, i.e. 60LATP). Therefore, it may be suggested that for large LATP content, where the O/Li ratio decreases, Li+ ion crowding about ether oxygen reaches to a saturation. In such a situation polymer as well as LATP surface states contribute significantly to conductivity. For very large salt content, a significant decrease of K-edge energy readily suggests Li+ ions using the surface and in grain pathways for electrical transport. Thus for high LATP content it is in fact the polymer that lies between the NASICON grains and improves the inter grain transport. Impedance spectroscopy and preliminary XPS investigations indeed complement XANES studies. These investigations suggest that addition of LATP nano crystallites affect electrical transport by providing pathways for Li+ ion conduction. Similar results were also obtained for XANES investigations on Na+ ion based polymer electrolytes. Acknowledgement: This work is supported by UGC-DAE-CSR, Indore, India under CRS scheme CSRIC-BL-52/CRS- 169/2016-17/833 The authors are grateful to Indus-II BL-1 facility of RRCAT, Indore, India and Mr Rakesh Kumar Sah for SXAS characterization. Special thanks to Prof Dr. Mukul Gupta, Scientist F, UGC-DAE-CSR for discussion and support in data analysis. The authors are grateful to Indus-II BL-14 facility of RRCAT, Indore, India and Mr R. K. Sharma for XPS characterization. Reference: + [1] M.D. Singh, B. Nayak, B. Choudhury, A. Sarit, A. Dalvi, Li -NASICON crystallites in PEO-LiCF3SO3 matrix: Characterization of a novel hybrid electrolyte, Solid State Ionics. 311(2017) 20-25. [2] M. D. Singh, A Dalvi, D M Phase PEO-NaI-NASICON hybrid polymer nanocomposites: An Assessment of Electrical Transport using Impedance and X-Ray Absorption Spectroscopy Materials Research Bulletin (2019)- Under review 28

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-25: Investigation of chemical and electronic properties of low

dimensional TiO2 films

C. P. Saini1, A. Barman1, D. Banerjee1, M. Gupta2, D. M. Phase2, D. Kanjilal3, A. K. Sinha4, A. Kanjilal1

1Department of Physics, School of Natural Sciences, Shiv Nadar University, NH-91, Tehsil Dadri, Gautam Buddha Nagar, Uttar Pradesh 201314, India 2UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore, Madhya Pradesh 452001, India 3Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067, India 4Indus Synchrotron Utilization Division, Raja Ramanna Center for Advanced Technology, Rajendra Nagar, Indore, Madhya Pradesh 452013, India Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected]

The low-dimensional metal oxide structures and the fabrication of their devices demand an in- depth knowledge of defects, especially oxygen vacancies (OVs), as they play a crucial role in controlling the structural, electrical and optical properties. This is particularly important for titanium oxide (TiO2) not only for fundamental interest, but also for a wide range of applications ranging from light-emitting devices to energy harvesting and storage. We demonstrate the efficacy of self-assembled nanostructures in TiO2 films for possible memory and photonics applications by tailoring the processing technique. In fact, while the controlled ion beam implantation technique is shown to be suitable for fabricating low power and high speed resistive random access memory devices [1,2], the growth of nanostructured films on chemically etched Si wafers is promising for photonic application with enhanced hydrophobicity [3-5]. Since OV is considered to be the key factor in these systems, a thorough exploration of the chemical properties has been carried out by X-ray photoelectron spectroscopy, where the X-ray Absorption Spectroscopy at Ti-K, L and O-K edges sheds light on the formation of OVs via reduction of ligand field splitting through demolishing TiO6 octahedral symmetry. This experience has recently been extended to surface enhanced photocatalytic activity for degrading the aqueous solution of methylene blue [6].

The authors would like to acknowledge the financial support from Shiv Nadar University and the Alexander von Humboldt Foundation. The help received from the scientists at IUAC, New Delhi, and RRCAT, Indore, is acknowledged.

References (example) [1] A. B. Barman, et al., J. Phys. D: Appl. Phys. 50, 475304 (2017). [2] A. B. Barman, Appl. Phys. Lett. 108, 244104 (2016). [3] C.P. Saini et al., J. Phys. Chem. C 121, 11448 (2017). [4] C.P. Saini et al., Appl. Phys. Lett. 108, 011907 (2016). [5] C.P. Saini et al., J. Phys. Chem. C 121, 278 (2017). [6] D. Banerjee, et al., Appl. Phys. Lett. 113, 084103 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-26: Material characterization using synchrotron Radiation P. R. Sagdeo1 1Department of Physics Indian Institute of Technology Indore, Indore, 453552, India; Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected]

Indus beamline(s) Used: ADXRD, EXAFS, SXAS

Abstract: Synchrotron radiation is known for its potential in material characterization. From last five years the research group working at material research laboratory IIT Indore using synchrotron radiation facilities and estimated various important parameters such as crystallographic octahedral tilt angles (ADXRD @ BL12), oxidation states of transition metal ions (XANES @ BL12 and BL9) and relative concentration of Fe mixed valent ions using soft X-ray absorption spectroscopy @BL1. The obtained results have been compared with the standard techniques and found to be consistent.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-27: Epitaxial Lattice-Matched TiN/(Al,Sc)N Metal/Semiconductor Superlattices for Thermionic Energy Conversion Bivas Saha International Centre for Materials Science & Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064, INDIA Email: [email protected]

Indus Beamline(s) Used: BL 01 of Indus 2, BL: 10, BL: 14

Since the 1960s, researchers exploring the potential of artificially-structured materials for applications in quantum electronic devices have sought combinations of metals and dielectrics that could be combined on the nanoscale with atomically-sharp interfaces. Early work with multilayers of polycrystalline elemental metals and amorphous dielectrics showed promise in tunneling devices. More recently, similar metal/dielectric multilayers have been utilized to demonstrate novel optical metamaterials. These metal/dielectric multilayers, however, are not amenable to atomic-scale control of interfaces. We developed the first epitaxial nominally single crystalline metal/semiconductor superlattices that are free of extended defects. These rocksalt nitride superlattices have atomically sharp interfaces and properties that are tunable by alloying, doping and quantum size effects. Furthermore, these nitride superlattices exhibit exceptional mechanical hardness, chemical stability and thermal stability up to ~1000C.

In this presentation, I will describe growth, structural characterization and transport properties of epitaxial TiN/(Al,Sc)N metal/semiconductor superlattices for their thermionic energy conversion and optical metamaterial applications. Since Schottky barrier height at metal/semiconductor interfaces control current flow across cross-plane (growth) directions in superlattices, synchrotron based X-ray photoemission spectroscopic measurements, along with first-principles modeling analysis are performed to determine valence band offset, band alignments and the Schottky barrier height. Moreover, the carrier concentration of semiconducting layers are tuned with dopants to control the depletion width and semiconductor band bending at the interfaces. The effects of dopants on the energy band structure of the semiconductor are also analyzed to gain insights into the Schottky barrier formation and its experimental determination.

References.

1. B. Saha, A. Shakouri and T. D. Sands, "Rocksalt Nitride Metal/Semiconductor Superlattices: A New Class of Artificially-Structured Materials". Appl. Phys. Rev. 5, 021101 (2018). 2. S. Nayak, S. Acharya, M, Baral, M. Garbrecht, T. Ganguli, S. M. Shivaprasad and B. Saha, "Interfacial Band Alignment and Schottky Barrier Height of Epitaxial Lattice-Matched TiN/Al0.72Sc0.28N Metal/Semiconductor Superlattice Interfaces for Thermionic Energy Conversion” (In-review, 2019). 3. S. Nayak, M. Baral, M. Gupta, J. Singh, M. Garbrecht, T. Ganguli, S.M. Shivaprasad and B. Saha, "Rigid- Band Electronic Structure of Scandium Nitride (ScN) across the n to p–type Carrier Transition Regime " (In-review, 2019).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-28: 4f magnetism in rare-earth intermetallics studied using photoelectron spectroscopy at Indus Synchrotron.

Soma Banik Synchrotron Utilization Section, Raja Ramanna Centre for Advanced Technology, Indore, 452013, India e-mail: [email protected]

Indus beamline Used:1) AIPES beamline BL-2, Indus-1 and 2) ADXRD beamline BL-12, Indus-2.

The ground state properties of rare-earth based intermetallics depend on the nature of 4f-electrons and the strength of hybridization of 4f-electrons with delocalized band states. To understand the origin of magnetism in these systems, it is extremely important to probe the density of 4f-electrons experimentally. In this talk, I will present the valence band results of rare-earth systems like CeAg2Ge2 and PrGe where the partial density of 4f states has been probed using widely tunable photon energy at Indus synchrotron source. Both the system has anisotropic magnetic properties with an antiferromagnetic ordering in CeAg2Ge2 and a complex magnetism in PrGe. Partial density of Ce 4f states, showed both localized and itinerant character [1] with less hybridization strength between the 4f and the conduction electrons responsible for the antiferromagnetic ordering. However, complex magnetism in PrGe is due to the strong hybridization of the Pr 4f electrons with the conduction electrons that causes change in spin polarization across the magnetic ordering [2]. Temperature dependent crystal structure studies using synchrotron source showed that the magnetic transition is first order like in both the systems. Modification in the electronic structure which drives the magnetism in these rare-earth systems will be discussed here.

References: [1] Soma Banik, Aparna Chakrabarti, Devang A. Joshi, A. Thamizhavel, D. M. Phase, S. K. Dhar, S. K. Deb, Physical Review B 82, 113107 (2010). [2] Soma Banik, Pranab Kumar Das, Azzedine Bendounan, Ivana Vobornik, A. Arya, Nathan Beaulieu, Jun Fujii, A. Thamizhavel, P. U. Sastry, A. K. Sinha, D. M. Phase & S. K. Deb, Scientific Reports 7, 4120 ( 2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-29: Study of medium range ordering in metal-metalloid glass using synchrotron x-ray diffraction

S. N. Kane1, K. Gehlot1, A. K. Sinha2 1 Magnetic Materials Lab., School of Physics, D. A. University, Khandwa road, Indore-452001 2 Indus Synchrotrons Utilization division, RRCAT, Indore 452013, Presenting, Corresponding Author’s Email:[email protected] Indus beamline(s) Used: BL-12 Study of metallic glasses has always been very fascinating for researchers since they came into existence, owing to their superior properties, as compared to their crystalline counterparts. Changes in ordering affects the properties of metallic glasses. Radial Distribution Function RDF (obtained by Synchrotron XRD measurements) can be effectively used for computing information on 1st, 2nd near neighbor shell, and medium range order (MRO) in TM-M class of metallic glasses. Various compositions, and treatments (thermal annealing, ion irradiation) were studied through SXRD measurements, to monitor changes in ordering. Results clearly display irradiation induced changes in medium range order, surface morphology and magnetic properties, although short range order gets rather un-affected. Irradiation effect is seen in the form of enhanced surface roughness. Observed minor changes in magnetic properties are accounted for irradiation induced structural changes. Parabolic variation (shown via an empirical relation) between interatomic distances for 2nd, 3rd co-ordination shell and magnetization, suggests strong correlation between structural, magnetic properties. Detailed results will be presented.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-30: Multiferroicity and magnetoelastic coupling in α-Mn2O3

M. Chandra1, S. Yadav1, R. J. Choudhary1, R. Rawat1, A. K. Sinha2, M-B Lepetit3,4 and K. Singh* 1UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore - 452001, India 2 HXAL, Synchrotrons Utilization Section, RRCAT, Indore 452013, India 3 Institut Néel, CNRS UPR 2940, 25 av. des Martyrs, 38042 Grenoble, France 4Institut Laue Langevin, 72 av. des Martyrs, 38042 Grenoble, France

Presenting Author’s Email:[email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: BL-12

The multiferroics where at least two primary ferroic orders are present and coupled in a single system constitute an important class of materials. They attracted special consideration as they present both intriguing fundamental physics problems and technological importance for potential multifunctional devices. Here, we present the evidence of multiferroicity and magnetoelectric (ME) coupling in α-Mn2O3. Corresponding to the antiferromagnetic (AFM) ordering around 80 K, a clear frequency independent transition is observed in the dielectric permittivity. We showed that electric polarization emerges near AFM regime that can be modulated with magnetic field. The detailed structural analysis using synchrotron radiation X- ray diffraction demonstrates the increase in structural distortion with decreasing temperature, as well as changes in the unit cell parameters and bond lengths across the ferroelectric and magnetic ordering temperatures. This observation of multiferroicity and magnetoelastic coupling in α-Mn2O3 provides insights for the exploration of ME coupling in related materials.

Authors are very much thankful to Dr. Archana Sagdeo and Mr. M. N. Singh for their help during low temperature SXRD measurements.

*Presently at Dr. B.R. Ambedkar National Institute of Technology, Jalandhar.

Reference [1] M. Chandra, S. Satish, R. J. Choudhary, R. Rawat, A. K. Sinha, M-B Lepetit and K. Singh, Phys. Rev. B 98, 104427 (2018). 34

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-31: Utilization of Indus Synchrotrons Beam lines for basic understanding and development of non-traditional magneto-electric materials R.N. Bhowmik 1Department of Physics,Pondicherry University,R.V. Nagar, Kalapet, Pondicherry-605014, India Corresponding Author’s Email: [email protected]; [email protected]

Indus beamline(s) Used: Dr. Anil Kumar Sinha (collaborator), Beam line 12, Indus-2 In the last five years, my research group in the department of Physics, Pondicherry University, is actively involved in studying the effect of structural phase heterogeneity on tuning the magnetic, dielectric, electronic, ferroelectric and magneto-electric properties of various types of magnetic oxides and their composites [1-5]. Recently, we are focused to translate the basic understanding of these materials for the development of non-traditional magneto-electric materials, where properties can be controlled by application of both magnetic and electric fields [6]. Such materials are being modified in different nano-structured forms, e.g., thin film/multi-layered metal doped hematite, composite of ferrimagnetic particles in ferroelectric matrix, nanocrystalline hexaferrite and double perovskites, to test their suitability for the applications in next generation spintronics devices, permanent magnets and data storage devices, etc. In this connection, experimental facilities in Synchrotrons beam lines (BL-12) and other units of Indus-2, Indore are being extensively used to precisely determine the structural phase (cell parameters, valence state of caions, phase) and enabled us to take up few challenging problems in relatively less investigated systems of metal doped hematite (rhombohedral structure) and Co rich spinel oxides. For example, synchrotron X- ray diffraction (SXRD) patterns have confirmed stabilization of Rhombohedral structure in Ga doped hematite system, prepared by mechanical alloying and chemical routes. This system has exhibited enhanced ferromagnetism, magneto-conductivity, negative differential resistance, and electric field controlled magnetism [3, 6]. It has been possible to confirm the existence of tetravalent Fe4+ state in Co rich spinel oxides using X-ray absorption near edge structure spectroscopy (XANES) measurements and determine the phase percentage in self-composite structure of Co-rich spinel ferrite [1, 2]. A joint research work is in progress to establish a correlation between lattice structure and magneto- electric properties by extensive utilization of the Indus synchrotrons beam line facilities (SXRD measurements 4-870 K, XANES, EXAFS, XMCD, XPS, X-ray reflectivity (XRR) and TXRF (total reflection X-ray fluorescence)) and studying the magnetic, electric and ferroelectric properties on nanocrystalline, composite and thin film/multi-layered structured materials. Some of the materials will be identified to verify their suitability for the room temperature applications. I express my sincere thanks to Dr. Anil Kumar Sinha (BL-12) for extending all possible supports in my journey for basic understanding of non-traditional materials in Pondicherry University.

References

[1] R.N. Bhowmik et al., J. Alloys Compd. 646, 161 (2015). [2] R.N. Bhowmik et al., J. Alloys Compd 680, 315 (2016). [3] R. N. Bhowmik, G. Vijayasri, and A. K. Sinha, RSC Adv. 6, 112960 (2016). [4] R.N. Bhowmik, and A.K. Sinha, J. Magn. Magn. Mater 421, 120 (2017). [5] R.N. Bhowmik, S. Kazhugasalamoorthy, and A.K. Sinha, J. Magn. Magn. Mater. 444, 451 (2017). [6] R.N. Bhowmik, A.G. Lone, J. Magn. Magn. Mater. 462, 105 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-32: Point Defect Identifications in III-Nitrides Using X-ray Absorption Spectroscopy

Sanjay Nayak1,2 1 Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore-560064, India 2Indo-Korea Science and Technology Center, Bangalore-560064, India

Point defects such as vacancies, interstitials, foreign impurities, etc. and line defects such as dislocations, grain boundaries, etc. significantly impact the physical properties of an otherwise perfect semiconductor. Electronically active point defects such as intentional doping of n-type (electron) and p-type (hole) carriers as well as native defects such as vacancies and impurities introduce defect states inside the bandgap of a semiconductor with shallow and/or deep characteristics. Thus, control of defects in semiconducting materials is crucial for engineering its structural, electronic, and optoelectronic properties. However, control of defects need it's knowledge of origin. Experimental identification of the point defect is very difficut and thus results obtained with first-principles based total energy calculations has been taken as reference. Our recent studies reveal that a combine study of XAS and DFT calculations is much more powerful in determining the dominant point defects in thin films where we analyze the experimentally acquired XANES spectra by co-relating them with results of first-principles simulations of various defect complexes and decipher the characteristic features. In this presentaion, I will emphasize on such defects identification in two technologically important III-Nitrides semiconductors (i.e. GaN, ScN) and highlight the limitations of these techniques. More specifically, I will speak on the microscopic origin of blue light in Mg doped GaN, one of the most controversial issues in the field of III Nitrides.

References [1] S. Nayak, M. Gupta, U. V. Waghmare, and S.M. Shivaprasad “Origin of Blue Luminescence in Mg-Doped GaN”, Phys. Rev. Applied 11, 014027 (2019).

[2] S. Nayak, M. Baral, M. Gupta, J. Singh, M. Garbrecht, T. Ganguli, S.M. Shivaprasad and B. Saha, “Rigid- Band Electronic Structure of Scandium Nitride (ScN) across the n to p–type Carrier Transition Regime” (In review, 2019).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-33: TAILORING OF ELECTRICAL AND OPTICAL PROPERTIES OF METAL DOPED TRANSITION METAL OXIDES

Ratnesh Gupta School of Instrumentation, Devi Ahilya Vishwavidyalaya, Indore, India. Email:[email protected]

Indus beamline(s) Used: INDUS-I AIPES, INDUS-II BL 1 SXAS, BL12 ADXRD

Bandgap engineering and surface nano structuring of TiO2 thin films play a crucial role in increasing its efficiency to get utilized in fabrication of sensors, optoelectronic devices and in various spintronic applications.[1-2] Precise control over the defects is needed to modify the binding energy of O-2p and Ti-3d states which can bring the change in bandgap and enhance the photocatalytic activity of these thin films.[3] In the present work, we present the electrical and optical properties of metal-doped TiO2 prepared by pulsed laser deposition and modify its properties using swift heavy ion irradiation with different ions. These films were irradiated with 100 MeV Au and Si ion beams at different fluences ranging from 5X1012 ions/cm2 to 1X1013 ions/cm2. Structural characterization shows that as-deposited films were amorphous in nature and no phase change has been observed with increasing ion fluence rather successive amorphization of the films as confirmed by angle dispersive X-Ray diffraction technique. Ion irradiation decreases the band gap energy of the film. Swift heavy ion irradiation enhances the oxygen vacancies in the film, and the extra electrons in the vacancies act as donor like states. In valence band spectrum, there is a shift in the Ti 3d peak towards lower energies and the shift is equivalent to the band gap energy obtained from UV spectrum. The detailed results will be discussed on the correlation of electronic structure of the film with its optical properties.

References:

[1] S.K.Zheng,T.M.Wang,G.Xiang,C.Wang, Vacuum 62, 361 (2001).

[2] Sagar Sen, Ajay Gupta, D.M.Phase, Ratnesh Gupta, Applied Surface Science 440, 403 (2018).

[3] C. P. Cheney, P.Vilmercati, E.W. Martin, M. Chiodi, L. Gavioli, M. Regmi, G. Eres, T. A. Callcott, H. H. Weitering, and N. Mannella, Phys. Rev. Lett. 112, 036404 (2014).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-34: Magnetic instability and f–d hybridization in doped CeFe2 S. K. Srivastava1, Rakesh Das2 and M. Gupta3 1Department of Physics, Indian Institute of Technology Kharagpur - 721302, India 2Department of Applied Science, Haldia Institute of Technology, Haldia - 721657, India 3UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore - 452 001, India Presenting Author’s Email: [email protected]

Indus beamline(s) Used: BL-1, Indus 2

RFe2 (R = Rare earth) compounds have been known for their multifunctional applications for more than three decades. CeFe2 is an unusual member of the RFe2 family in the sense that it has a relatively low paramagnetic to ferromagnetic Curie temperature (Tc1 = 230 K), an anomalously low lattice constant (7.3 Å), and a relatively small magnetic moment (~ 2.3 B/f.u.). Strong hybridization between Ce f and Fe d states has been reported to be the cause of these anomalies. A very small amount (~ 5 %) of certain impurities in CeFe2 is known to cause a loss of ferromagnetism, at a temperature Tc2 below Tc1, to an antiferromagnetic state via a first-order transition. Thus, CeFe2 lies on the verge of a magnetic instability. However, the proposed mechanisms for what drives this instability are still speculative. One such speculation is the impurity induced modification of the f-d hybridization. The subject of this talk is the investigation of the applicability of this very hybridization-based mechanism for the magnetic instability. For the investigations, the following two-fold approach has been adopted: (i) a computational study of a possible systematics of the variation of the f-d hybridization for a number of appropriate impurities spanning the periodic table [1], and (ii) for a particular impurity, an experimental exploration of the manifestation of a possible connection between the impurity induced changes in the hybridization and the occurrence of the second phase transition [2]. The X-ray absorption spectroscopy performed in the BL-1 of the INDUS2 synchrotron has particularly been useful in the latter study.

References

[1] Das, Rakesh, Das, G.P. and Srivastava, S.K.: Electronic structure and local magnetism of 3d–5d impurity substituted CeFe2, J. Phys. D: Appl. Phys. 49, 165004 (2016). [2] Das, Rakesh, Gupta, M. and Srivastava S.K.: Magnetic and Spectroscopic properties of Cr, Ag and Au doped CeFe2 compounds, J. Magn. Magn. Mater. 433, 162 (2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

IT-35: Prompt Screening of the alterations in biochemical and mineral profile of cereal crops stressed with heavy metals and metal oxide nanoparticles using synchrotron radiation based X-ray and infrared spectroscopic probes K N Uttam Saha’s Spectroscopy Laboratory, Department of Physics, University of Allahabad, Allahabad Email: [email protected]

Rapid urbanization, technical advancements, accelerated rate of industrialization, extensive mining activities, intensive agricultural practices and unsustainable use of natural resourceshave caused a grave concern related with the contamination of essential component of life especially floral community with heavy metals and their modified forms like nanoparticles. Heavy metals and nanoparticles are known to alter the biochemical and elemental profile of plants and negatively affect its growth, development and productivity. This necessitates early diagnosis of stress of heavy metals and nanoparticles in plants in vivo in order to reduce the associated risks and restore the yield. Plant diagnosis till date relies mostly on tissue destructing methodologies that involve protocols for extracting and dissolving the desired biochemical in reagents, solvents and acids. These protocols are time consuming, labour intensive and cost ineffective. These procedures often dilute the chemical/elemental species beyond the detection limit of the instrument and disturb the native configuration of chemicals and molecules under consideration. In this scenario, comprehensive and rapid screening technologies are required that have the potential to detect physiological, biochemical and morphological characteristic of plants non- destructively and promptly at an early stage of plant growth and development. Unlike conventional wet analyses, the advances in synchrotron radiation based X- ray techniques can be exploited as investigation probes for the detection of elemental and biochemical distribution that can lead to a better understanding of the interaction mechanisms and fate of metals and nanoparticles in the plants. Synchrotron radiation source is characterized by high brightness, intensity, polarization, collimation, low emittance and widely tenability. Synchrotron radiation based spectroscopy techniques like micro X-ray fluorescence X-ray imaging and infrared micro-spectroscopy are capable of detecting the alteration in the cellular constituents of plants rapidly in situ with high accuracy. These techniques require minimal sample preparation and are nondestructive in natures with high sensitivity at ppb level. Keeping this view in mind, diagnosis capability of synchrotron radiation based techniques have been demonstrated by exogenously applying heavy metals like manganese, copper, cadmium, chromium and metal oxide nanoparticles like copper oxide nanoparticles, titanium dioxide, aluminum oxide and zinc oxide on mineral content of cereal plants by recording the X-ray fluorescence spectra, infrared spectra and X-ray images of stressed plant tissues at synchrotron utilization section, RRCAT, Indore. The analysis of the spectral information and images from these spectroscopic techniques shows that the heavy metals and nanoparticles interact with the biochemical and elemental constituents of the plants in a complex manner. Some representative energy dispersive X- ray fluorescence spectra, infrared spectra and X-ray imaging records excited by synchrotron radiation will be discussed during the presentation.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

Contributory Presentations

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P01: Correlation of electronic structure with resistive switching and ferroelectric behavior of Ca-doped Bi0.90ca0.10Feo3 films: a strain dependent study

Sadaf Jethva1, Savan Katba2, Mukul Bhatnagar3,4, Mukesh Ranjan4, Dinesh Shukla5, R.J. Choudhary5, D.M.Phase5 and D.G.Kuberkar1* 1Department of Nanoscience & Advanced Materials, Saurashtra University, Rajkot-05,India; 2Department of Physics, School of Science, RK University, Rajkot-360020, India; 3Department of Physics,University università degli studi di genova, Italy 4FCIPT, Institute for Plasma Research, Sector-25, Gandhinagar - 382044, India 5UGC DAE Consortium for Scientific Research, Khandwa Road, Indore –452017, India Presenting Author’s Email:[email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: INDUS – 2, BL-1 SXAS

Role of thickness induced structural strain in modifying the crystal structure and electronic structure, I-V hysteresis and ferroelectric properties of PLD grown Bi0.90Ca0.10FeO3 (BCFO) films have been systematically studied. Structural study carried out using XRD and ɸ- scan measurements confirm that, all the films are epitaxially oriented in (100) direction. Room temperature absorption spectra shows the presence of asymmetric broad peak around ~2.5 eV indicative of the presence of defect states inside the band gap and is attributed to the oxygen vacancies. The spectral shape of Fe L3,2 – edge XAS spectra measured for all the films is similar to that of Fe2O3 reference spectrum indicating that, Fe- ions are present in trivalent state with octahedral crystal field symmetry. Normalized O K- edge XAS spectra of BCFO films show a significant change in the O 2p states hybridized with the Fe 3d, Bi 6s, and Ca 4s states in the conduction band. Increment in Fe3d – O2p hybridization and localization of the Fe3deg/Bi6s-O2p orbitals play an important role in the improvement in the ferroelectric behavior, in addition to the decrement in oxygen defect states. The change in the Schottky barrier height/width and charge trapping/detrapping of electrons by oxygen vacancies near interface region is responsible for the resistive switching (RS) behavior of the film under study.

(a) a d 2 b

c

a

1 Mixing of Fe4sp, Ca2sp -O2p

BCFO 23nm Bi6s -O2p 43nm 63nm Fe3d -O2p Fe O 2 3 525 530 535 540 545 550 555

BCFO e (b) 23nm g b 43nm t 63nm 2g Normalized Intensity (a.u) Fe O 2 3 a a 2 1

Bi6s -O2p

Fe3d -O2p 526 528 530 532 534 536 Photon energy(eV) 41

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P02: Transition Metal Grafted Graphene Oxide for Selective Oxidation of Benzyl Alcohol: XPS and DFT Study

Ravi Vithalania, Dikin Patela, Chetan K. Modia,*, Narayan N. Somb, Prafulla K. Jhab, S. R. Kanec aApplied Chemistry Department, Faculty of Technology & Engineering, The Maharaja Sayajirao University of Baroda, Vadodara-390 001, Gujarat, India bDepartment of Physics, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara-390 002, Gujarat, India cIndus Synchrotrons Utilisation Section, Raja Ramanna Centre for Advanced Technology, Indore-452013, India Presenting/ Corresponding author: [email protected] Indus beamline(s) Used: XPES (BL- 14) Chemo-selective oxidation of benzyl alcohol (BzA) to benzaldehyde (BzH) was built up using transition metal grafted graphene oxide [ML-f-GO (M=VO4+, Co2+, Cu2+)]. Engagement of surface hydroxyl groups on GO in the fabrication of ML-f-GO was confirmed by density functional theory (DFT), FTIR, XPS, XRD, TGA, BET, Raman, SEM, and TEM. DFT study was executed in an attempt to elucidate the replacement of -OH groups by amino groups. The tendency of binding energy was -COOH > C-O-C> -NH2 > -OH which very well corroborate the belief developed from different characterization techniques that the amino groups of substituted amino functionalized moieties replace only surface hydroxyl groups of GO. Catalytic aptitude of the as-prepared catalysts was weigh-up against oxidation of BzA using 30% H2O2 as a greener oxidant. The impact of distinct parameters influencing catalytic activity has also been studied. Under the optimized conditions, CuL-f-GO was proven excellent with 99.5% yield of BzH.

Full range XPS spectra Cu 2P XPS spectra Calculated binding energy of graphene sheet functionalized by different groups.

Acknowledgments The authors would like to present his deep thanks and gratitude to Dr. R. J. Choudhary, UGC- DAE Consortium for Scientific Research, Indore for the help in carrying out work on the Indus- 1 synchrotron source.

References Ravi Vithalani, Dikin Patel, Chetan K. Modi*, Narayan N. Som, Prafulla K. Jha, S. R. Kane, Diamond & Related Materials 90 (2018) 154–165.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P03: Investigation of Buried Planar Interfaces in Multi-layered Inverted Organic Solar Cells Using X-ray Reflectivity

S. B. Srivastava1, M. H. Modi2, S. K. Ghosh1 and S. P. Singh1 1Department of Physics, Shiv Nadar University, Gautam Buddha Nagar 201314, India; 2X-ray Optics Section, Raja Ramanna Centre for Advanced Technology Indore 452013, India Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected]

Indus beamline(s) Used: BL-3 The hole and electron extracting interlayers in the organic solar cells (OSCs) play an important role in high performing devices. The present work focuses on an investigation of Zinc oxide/bulk heterojunction (ZnO/BHJ) and BHJ/MoO x (Molybdenum oxide) buried planar interfaces in inverted OSC devices using the optical contrast in various layers along with the electrical measurements. The x-ray reflectivity (XRR) analysis demonstrates the formation of additional intermixing layers at the interfaces of ZnO/BHJ and BHJ/MoO x (see figure below). Our results indicate infusion of PC71BM into ZnO layer up to ~4 nm which smoothen the ZnO/BHJ interface. In contrast, thermally evaporated MoO xmolecules diffuse into PTB7-Th dominant upper layers of BHJ active layer resulting in an intermixed layer at the interface of MoO x /BHJ. The high recombination resistance (~5 kΩ cm2) and electron lifetime (~70 μs), obtained from the impedance spectroscopy (IS), support such vertical segregation of PTB7-Th and PC71BM in the active layer. The OSC devices, processed in ambient condition, exhibit high power conversion efficiency of 6.4%. We consider our results have great significance to understand the structure of buried planar interfaces at interlayers and their correlation with the electrical parameters representing various interfacial mechanisms of OSCs [1].

Figure: X-ray reflectivity data (left) from multi-layered inverted solar cell and corresponding optical density (Right).

References

[1] S. B. Srivastava, M. H. Modi, S. K. Ghosh and S. P. Singh, J. Phys.-Cond. Matt 31, 124003 (2019)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P04: Electronic Structure of NiPO4 - Decorated Graphene Oxide for Photocatalytic Hydrogen Production

N. Chouhan1 and N. Gurbani1 1Department of Pure and Applied Chemistry, University of Kota, Kota-324005,India

Presenting Author’s Email: [email protected]

Indus 2 beamline(s) to be Used: BL-8 and BL-9

The synthesis and photoelectrochemical study of a hydrogen evolving catalyst i.e. NiPO4 modified graphene oxide (NGO), is reported. NiPO4 -anchored to graphene oxide (NGO) was synthesized by a one-pot in situ photoassisted method under visible-light irradiation by varying 0.00, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50 and 2.00 NiPO4: GO ratio, which was achieved without the addition of surfactant or a structure-directing reagent. NGO nanosheets showed noticeably improved photocatalytic activity due to the staggered heterojunction (type II) system, where photoinduced electrons transferred from NiPO4 to the GO sheets that result in decreased charge recombination. Out of the series of the samples, nanocomposite 0.75 NiPO4: GO, shows the optimum hydrogen production -1 -1 activity (0.817896 mmol H2 g h ) towards water splitting in the visible range of solar light. On the basis of the X-ray diffraction, UV Vis spectroscopy, X ray absorption (at O K-edge, C K-edge, Ni K-edge and P K-edge), raman spectroscopy, FT Infra red spectroscopy, electron spin resonance spectroscopy, and time resolved spectroscopy the electronic environment of the synthesised samples are studied. The results of above studies go hand in hand and are supported by the reasonably good spin concentration due to the presence of a large amount of the free-radical-like carbon, long-range direct/indirect exchange or interaction between graphene matrix, fragmented graphitic zones, C-defect nonbonding localized electronic states, and flat-band quasi-localized (QL) states induced by the point defects in lattice.

Key words: hydrogen production, electronic structure, water splitting, nickel phosphate anchored graphene oxide

References

[1] N. Gurbani, C.-P. Han, K. Marumoto, R.-S. Liu, R. J. Choudhary, N. Chouhan ACS Appl. Energy Mater. 1(11), 5907 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P05: Surface Characterisation of 1,5diphenylcarbazide Immobilized cross- linked Chitosan films using XPS

P. S. Kulkarni1, S. D. Kulkarni2 1Post-graduate and Research Centre, Department of Chemistry, MES Abasaheb Garware College, Pune -411002, India 2Post-graduate and Research Centre, Department of Chemistry, Sir Parashurambhau College, Pune - 411030, India Presenting and Corresponding Author’s Email: [email protected] Indus beamline(s) Used: INDUS Beamline 2, AIPES Indus beamline(s) Used: INDUS Beamline 2, AIPES In the present study the significant enhancement in the adsorption capacity of Gluteraldehyde cross-linked chitosan films through immobilization of 1,5diphenylcarbazide (DPC) towards Cr (VI) was studied adsorption studies suggested that the removal of Cr (VI) is spontaneous process occurring mainly through pore diffusion process with a removal capacity of 166 mg-1 . XPS analysis of Cr (VI) treated film indicates formation of Cr (VI) – DPC complex on the surface of film as well as presence of predominantly adsorbed Cr (III) species. XPS analysis of Cr (VI) treated film was carried out at INDUS-2 Synchrotron UGC-DAE Consortium Indore to ascertain the nature of adsorbed Cr (VI) species as well as surface characteristics of the film. It was confirmed by XPS that the DPC bound Cr (VI) was reduced to Cr (III) with oxidation of diphenylcarbzide to corresponding carbazone which creates a concentration gradient between the solution and the surface of the film that results into a spontaneous flow of Cr (VI) ions from solution into the film. Thus the present study clearly demonstrate that incorporation of selective chelating agents such as DPC within the films significantly improves its removal capacity for a metal ion such an engineered film may be regarded as a low cost biodegradable material that has potential applications in membrane filtration technology.

XPS analysis of (a) carbon, (b) chromium, (c) nitrogen and (d) oxygen regions

Acknowledgement: Authors are also grateful to UGC-DAE consortium Indore for XPS analysis; CIF, S.P.P.U., Pune for FE-SEM, IR and EDS analysis and NCL, Pune for Contact angle measurements

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P06: Non-destructive and rapid interrogation of response of wheat seedlings towards Al2O3 nanoparticles stress using attenuated total reflectance Fourier transform infrared spectroscopy and X-ray fluorescence excited by synchrotron radiation Sweta Sharma1, A. K. Singh2, M. K. Tiwari2 and K N Uttam3 1Department of Botany, University of Allahabad, Allahabad-211002, India 2Synchrotron Utilization Section, Raja Ramanna Centre for Advanced Technology, Indore 3Saha’s Spectroscopy Laboratory, Department of Physics, University of Allahabad, Allahabad 211002, India Email: [email protected]

Indus beamline(s) Used: INDUS-2, Micro X-ray Fluorescence (Beamline-16) There has been tremendous development in the field of nanotechnology and consequently the release of nanoparticles in the environment and its interaction with the biotic components is inevitable. However, knowledge concerning nanomaterial biosafety, adverse effects, fate, and acquired biological reactivity is still at infancy and requires further scientific efforts to assess their possible nano-agricultural risks. Therefore, the present study aims to reveal the molecular and elemental alterations in the leaves of the wheat seedlings caused by direct exposure of Al2O3 NPs in non-destructive and rapid manner using attenuated total reflectance Fourier transform infrared spectroscopy and X-ray fluorescence excited by synchrotron radiation. For this, the wheat seedlings have been grown in sand matrix under controlled growth conditions and the toxicity of Al2O3 NPs has been introduced at different concentrations (0.2-1.6 mM). For analyzing the alterations in the elemental profile, X-ray fluorescence spectra of the leaves of the control and Al2O3 NPs treated wheat seedlings have been recorded by synchrotron radiation X-ray of energy 10 keV. The analyses of the recorded spectra show the presence of elements phosphorus, sulphur, chlorine, potassium, calcium, manganese, iron, copper, nickel and zinc. A calibration free approach, PyMca has been used for the quantitative estimation of the detected elements in the leaves of the control and Al2O3 NPs treated wheat seedlings. The excess supply of Al2O3 NPs to wheat seedlings results in the accumulation of aluminum in the leaves of the seedlings. The accumulation of aluminum in wheat seedlings negatively affects the uptake and translocation of phosphorus, sulphur, calcium, manganese, iron, copper and zinc while it has stimulating effect on the uptake of chlorine and potassium. For determining the biochemical alterations, the infrared spectra of the leaves of control and Al2O3 NPs treated seedlings have been recorded in the wavenumber 4000- -1 400 cm . The PCA of control and Al2O3 NPs treated seedlings. The treatment of Al2O3 NPs enhances the spectral features of cellulose, hemicelluloses, lignin, lipids, amino acids, proteins carbonyl, and pectin in the leaves of wheat seedlings. The increase in the area of these molecules indicates the physiological significance of these molecules in the modulation of Al2O3 NPs stress in the wheat seedlings. The study adds substantive spectral data base to the existing elusive knowledge of nanotoxicity especially Al2O3 NPs to the plants and provides a molecular mechanism that defines the occurrence of biochemical changes and defense strategy of plants towards Al2O3 NPs toxicity.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P07: Investigations on M'M''xenes as Topological Insulator Deependra Parajuli 1 and K. Samatha2 1 Ph. D. Scholar, Department of Physics, College of Science & Technology, Andhra University, Visakhapatnam-530003, India 2 Professor, Head and Suvervisor, Department of Physics, College of Science & Technology, Andhra University, Visakhapatnam-530003, India Presenting Author’s email: [email protected] Corresponding Author’s email: [email protected] Indus Beamline to be used: Indus -1: Angle Resolved PES BL-3

Mxenes are 2D inorganic compounds of transition metal carbides, nitrides, or carbonitrides with few atomic thickness. These compounds are exploited for industrial, biomedical, electronic and energy storage devices. Due to their large spin orbit coupling (SOC) and Dirac like band at Fermi level, it is predicted that M'-M''xene (M' and M" are transition metals) can be used as Topological Insulator. Topological insulator is a new state of matter with insulating in bulk and superconducting in surface or edge state. In this work, we use Scanning Electron Microscope-Electron Dispersive Spectrometer (SEMEDS), X-Ray Diffraction Unit (XRD), Electron Spin Resonance Spectrometer (ESRS), Scanning Tunneling Microscope (STM), High Resolution Tunneling Electron Microscope (HRTEM), Fourier Transform Infrared Spectrophotometer (FTIR) and Angle Resolved Photoemission Spectroscope (ARPES) for analysing surface and energy spectrum for abundancy, crystal structure, magnetic properties, imaging surfaces at the atomic level, structure & morphology, infrared spectrum and electronic structure of solids, solid surfaces & interfaces respectively. The topological surface state of the mxene systems can also be analyzed with the help of the loop variable called Z2 invariant and Chern Number. We reviewed different theoretical models, material properties and experimental results of Topological Insulators in 2D and 3D phases. Surface electrons in Topological Insulator are superconducting due to absence of their backscattering. So, Mxene can be used in spintronic devices, transistors without dissipation for quantum computers based on Quantum Spin Hall Effect (QSHE) and Quantum Anamolous Hall Effect (QAHE) and other applications on advanced magnetoelectronic and optoelectronic devices as topological insulator. References:

[1] Khazaei, M. et. al. (2016).Topological insulators in the ordered double transition metals M2’M’’C2 Mxenes (M’ = Mo, W; M” = Ti, Zr, Hf), PHYSICAL REVIEW B 94, 125152 [2] Anasori, B. et al. (2016). Two-dimensional, ordered, double transition metals carbides (MXenes), ACS Nano 9, 9507.

M Γ M M Γ M

Figure 1. Edge band structures for Mo2TiC2O2 and W2HfC2O2.The Fermi energy is located at zero energy. Odd number of intersection of Fermi level shows that the material is non trivial topological insulator. For Mo2TiC2O2, there are 3 intersections and that for W2HfC2O2 is one. It is also obtained by Z2 index calculation. 47

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

Table: 1 SOC is on for SOC is on SOC is on SOC in on for all Remarks all elements for only M” for only M” elements with HSE06 (VASP/QE)

Mo2TiC2O2 0.041/0.036 0.027 0.009 0.119 The Spin orbit coupling

Mo2ZrC2O2 0.069/0.065 0.026 0.039 0.125 plays an important role

Mo2HfC2O2 0.153/0.151 0.027 0.120 0.238 for lifting the energy gap W2TiC2O2 0.136/0.135 0.121 0.010 0.290 for the non trivial property to generate W2ZrC2O2 0.170/0.166 0.123 0.040 0.280 0.285/0.285 0.135 0.140 0.409 topological insulator. W2HfC2O2

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P08: Aerobic oxidation of alcohols and homocoupling of arylboronic acids catalyzed by chitosan stabilized gold nanoclusters

K. Paul Reddy1, Ponnusamy Shanmugam2 and Arumugam Murugadoss1* 1Department of Inorganic Chemistry, University of Madras, Guindy Campus, Chennai – 600025, India. E-mail: [email protected] 2Organic and Bioorganic Chemistry Division, Council of Scientific and Industrial Research (CSIR) – Central Leather Research Institute (CLRI), Adyar, Chennai – 600020, India. E-mail: Email: [email protected] & [email protected] Though functional polymers either synthetic or natural have been effectively used as a stabilizer for the preparation of size controlled gold nanoclusters (NCs), loading of large amounts of gold NCs in the polymer support is one of the key challenges in the catalysis community as this may alter the size of the NCs by aggregation or prevent the dispersion of gold NCs in the reaction solutions due to processability of the polymers in the medium. Herein we present a synthesis of gram scale quantity of gold NCs supported on chitosan polymer with sizes in the range of 4-5 nm by simple mortar grinding. The chitosan supported gold NCs could be used as both quasi-homogeneous and heterogeneous catalysts for the aerobic oxidation of alcohols and homocoupling of the arylboronic acid, respectively in aqueous solution at room temperature. Interestingly, the large amount of gold NCs can be loaded into chitosan support and used as effective heterogeneous catalysts without altering the size of the gold NCs, which is in sharp contrast to previous reported methods.1-3 These catalysts exhibited excellent recyclability potential both in quasi-homogeneous and heterogeneous condition. X-ray photoelectron spectroscopy and HRTEM analysis reveals that chitosan could effectively stabilize the gold NCs, which is stable even after several time reusable and demonstrates that it could be used as potential catalysts in various functional group transformation reactions.

References [1] A.Murugadoss, H. Sakurai. J. Mol. Catal. A: Chemical 341, 1 (2011). [2] R. N. Dhital, Dhital, A. Murugadoss, H. Sakurai. Chem. Asian J. 7, 55 (2012). [3] S. Haesuwannakij, Y. Yakiyama, H. Sakurai, ACS Catal. 7, 2998(2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P09: Ni(salen)-derived NiO Nanoparticles@Carbon Matrix Supported Gold Nanoclusters Catalysts for Direct Methanol Fuel Cell

A. Catherine Swetha1, A. Murugadoss*1 11Department of Inorganic Chemistry, University of Madras, Guindy Campus, Chennai – 600025, India. Email: [email protected] & [email protected] Hybrid composites of carbonaceous materials and metal oxide nanoparticles (NPs) have attracted tremendous research interest because of their large available surface area, where the electrocatalytically active precious metal atoms are anchored effectively1. Herein, we report the synthesis of a gold NCs supported on NiO nanoparticles/carbonaceous matrix hybrid composites as an anode catalyst for direct methanol fuel cells (DMFC). Atomic or few clusters of metallic gold are embedded in the hybrid composites of NiO NPs and carbonaceous matrix, have been synthesized by simply pyrolyzing Ni(salen) (salen=N,N’- bis(salicylidene)-ethylenediamine) complex and HAuCl4 precursors. This supported Gold NCs with basic DMFC electrode interface exhibit reasonable electrocatalytic activity and stability compared to the conventional catalysts. In contrast to reported methods, NiO NPs/carbon matrix supported gold NCs shows excellent cycling stability for 100 cycles2 demonstrating these supported Au NCs could be used as the potential electrode for other electrochemical energy conversion applications.

References

[1] Jing Du, Fangyi Cheng, Shiwen Wang, Tianran Zhang, Jun Chen, Sci. Rep. 4, 4386(2014)

[2] S. Yan, S. Zhang, Y. Lin. J. Phys. Chem C 115, 6986(2011)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P10: Monoclinic to High Temperature Cubic Phase Transformation in Dy and/or Sm Doped HfO2 Sandeep Kumar1, Chandana Rath1 1School of Materials Science and Technology, Indian Institute of Technology (B.H.U), Varanasi- 221005, India Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected]

Hafnium oxide (HfO2) exhibits the monoclinic phase at room temperature, tetragonal phase between ~1700-2600 oC which eventually transforms to cubic o phase at temperatures above ~2600 C. Herein, we report sol-gel synthesized HfO2 nanoparticles possessing the monoclinic phase which transforms to the high temperature cubic phase after incorporating Dy and/or Sm ions. While incorporating 11 at% of Dy in HfO2 lattice stabilizes the cubic phase at room temperature, for Sm doped HfO2, the monoclinic phase successfully transforms to cubic phase after doping 12 at% of Sm. Le-Bail refinement of X-ray diffraction (XRD) patterns further confirms the monoclinic and cubic phase corresponding to space groups, P21/c and Fm͞ 3m, respectively. The monoclinic to cubic phase transformation is accompanied with an enhancement in lattice strain reducing the particle size as realized from

Williamson-Hall analysis. After doping 1 at% of Dy in HfO2, photoluminescence study reveals strong emission peaks in visible regions induced due to an energy transfer from the host to Dy3+ active ions. In contrast to single ion doping of either Dy or Sm, the cubic phase of HfO2 is completely stabilized at room temperature after simultaneous incorporation of Dy and Sm with a total concentration of 13 at%. Detailed discussion on the stabilization of the cubic phase of 4+ 3+ HfO2 has been presented considering the difference in ionic radius and valency of Hf , Dy and/or Sm3+ ions resulting in formation of oxygen vacancies.

References

[1] S. Kumar, S. B. Rai, and C. Rath, Phys. Chem. Chem. Phys. 19(29),18957–18967 (2017)

[2] S. Kumar, S. B. Rai, and C. Rath, J. Appl. Phys. 123(5), 055108 (2018)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P11: Se K edge XAFS measurements in 3d transition metal doped Topological insulator Bi2-xMnxSe3 R. R. Urkude1, A. K. Yadav2, S. N. Jha2, A. A. Deshmukh1 , U. A. Palikundwar1 1Department of Physics, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur, 440033, India 2Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai, 400085, India Presenting Author’s Email:[email protected]; Corresponding Author’s Email: [email protected]; [email protected] Indus beamline(s) Used: Scanning EXAFS (BL-9); Angle Dispersive XRD (BL-12)

Topological insulators (TIs) attracted a lot of attention in recent years. While in the bulk they behave like ordinary insulators, their surface states are quite extraordinary. The 2D topological surface states have a conical energy-momentum dispersion and spins of electrons are locked to their momentum. Such properties promise many applications in spintronics and quantum computing. Doping of topological insulators by magnetic ions breaks the time reversal symmetry and opens a gap in the energetic structure. This allows a long-range magnetic order, which may lead to a number of striking topological phenomena. Recently, transition metal (TM) doped TIs have been the focus for the studies due to the exotic quantum and magneto- electric effects exhibited by them, and their expected high potential technological applications. In this work, we have carried out a systematic study on 3d TM doped Topological insulator Bi2-xMnxSe3 (0 < x < 0.9). The samples of Bi2-xMnxSe3 have been successfully synthesized by precipitation method. The crystal structure of the samples was found to be rhombohedral with symmetry. The powder X-ray diffraction data were analyzed via the Rietveld refinement method. The lattice parameters and the atomic coordinates obtained from the refinements were used as inputs for the powder cell program to visualize the crystal structure of the samples. The unit cell consists of 15 atomic layers grouped in three quintuplets with Se–Bi–Se–Bi–Se order. The quintuplets are van der Waals bonded to each other by a double layer of Se atoms. This gap is larger than other interlayer distances in the structure and it is expected to host extrinsic atoms in the case of Mn doping. There are two possible symmetric positions within the gap – distorted octahedral and distorted tetrahedral. Both the positions are surrounded by Se atoms. Another possibility is that extrinsic Mn atoms can substitute Bi atoms. Here we report a systematic study of the local structural environment surrounding Se in the materials Bi2- xMnxSe3. EXAFS measurements were carried out on the Se K edge in transmission mode at Beamline BL-09 Scanning EXAFS of Indus-2 synchrotron source at Raja Ramanna Centre for Advanced Technology (RRCAT), India. Analysis of the Se K edge XAFS reveals a change in the local environment around Se due to doping of Mn in the compound. This may be due to substitutional as well as interstitial positions occupied by Mn atoms in the basic Bi2Se3 crystal structure. Our results point towards strengthening of the covalent character of the Mn-Se bond. This information will be helpful in understanding the exotic physical properties of magnetic impurity doped topological insulators.

One of the authors R. R. Urkude acknowledges Department of Science and Technology (DST) India, for the financial support under the women scientist scheme-A (WOS-A), SR/WOS- A/PM-1001/2014. Authors are also thankful to the INDUS-2, RRCAT, Indore, India for EXAFS measurements.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P12: Investigation of structural and magnetic properties of ferromagnetic films interfaced / alloyed with Ta Yasmeen Jafri1, Gagan Sharma1, Ajay Gupta1, Mukul Gupta2 and Surendra singh3 1Amity Centre for Spintronic Materials, Amity University, Noida- 201313, India 2UGC-DAE Consortium for Scientific Research, Indore- 452001, India 3Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai-400085, India Presenting Author’s Email- [email protected] Corresponding Author’s Email- [email protected] Indus beamline used - BL-01, Indus-2 (Soft X-ray Absorption Spectroscopy beamline) The emerging field of spintronic and magnetic devices requires exploration of new materials with enhanced properties. Ferromagnetic films being relatively lighter shows weak spin orbit interaction (SOI). Recent investigations reveal that the combination of these conventional ferromagnets with some heavy metal could lead to enhanced spin orbit interaction [1], high magnetocrystalline anisotropy and large coercivity, which are the requirements for permanent magnetic applications [2-3]. However, magnetic, structural and interfacial properties have not been investigated in detail for such systems. In the present work, Fe1-xTax films were deposited using magnetron sputtering for different concentration of Ta i.e. Fe95Ta05, Fe90Ta10 and Fe85Ta15. X-ray reflectivity and X-ray Diffraction measurements were used to investigate the structural properties of films. From MOKE measurements it has been observed that coercivity is increasing with increasing Ta concentration. With thermal annealing at 600oC, coercivity increases significantly (~ 150%) possibly because of removal of stresses in as-deposited films. From soft x-ray absorption spectroscopy measurements, performed near the absorption edge of Fe reveals the elemental profile with varying Ta concentration. Fe peak has been observed to split in two peaks. The peak at lower binding energy corresponds to Fe influenced by Ta incorporation, the intensity of which increases with increasing Ta concentration. The magnetic properties as elucidated from polarized neutron reflectivity measurements were co-related with the results as observed from x-ray measurements. In order to investigate the depth selective properties of ferromagnetic films (FM = Co/Fe) interfaced with Ta and to check the possible presence of magnetic dead layer at FM/Ta interface, wedge shaped FM films interfaced with Ta were deposited. XRR and MOKE measurements at various points along the length of wedge were done in order to study the thickness dependent evolution of magnetic properties. Authors are thankful to UGC-DAE CSR for financial aid through CRS project and Mr. Anil Gome, Mr. Layanta Behera and Mr. Rakesh Kumar Sah respectively for XRR, XRD and XAS measurements. References- [1] A. Hrabec, F. J. T. Gonc¸ alves,C. S. Spencer, E. Arenholz, A. T. N’Diaye,R. L. Stamps, and Christopher H. Marrows, PHYSICAL REVIEW B 93, 014432 (2016). [2] Alexander Edström, PHYSICAL REVIEW B 96, 064422 (2017). [3] T. R. Gao, Y. Q. Wu, S. Fackler, I. Kierzewski, Y. Zhang,2 A. Mehta, M. J. Kramer and I. Takeuchi, APPLIED PHYSICS LETTERS 102, 022419 (2013)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P13: XANES spectroscopy for understanding of ion transport mechanism in PEO-NaI-NASICON hybrid polymer nanocomposites

M. Dinachandra Singha, Anshuman Dalvia* and D. M. Phaseb a Department of Physics, BITS Pilani-Pilani Campus (RJ-333031), India b UGC-DAE Consortium for Scientific Research, Indore 452001, India Presenting Author’s Email: [email protected]; *Corresponding Author’s Email: [email protected]

Indus beamline(s) Used: Indus II , BL – 01, SXAS characterization & Indus II, BL-14, XPS study Trends of K-edge energies of oxygen and carbon in the X-Ray absorption near edge structure spectra with compositional variation have been found to be useful in proposing a mechanism for ionic transport in novel polymer hybrid composites. Thus the present investigation focuses on conductivity-structure correlation in two of the Na+ ion based polymer composites with different NASICON crystallites. The K edge energy values of ether oxygen and carbon of pristine PEO were found to be in agreement with the earlier reported data [1]. NTP i.e. NaTi2(PO4)3 embedded hybrid solid polymer composites were prepared in a wide range of composition 10NaI-90(PEO1-xNTPx) (wt%), for 0 ≤ x ≤ 0.7. A maximum ionic conductivity of ~ 4 x 10-5 Ω-1cm-1 has been achieved with x = 0.7 at 40 oC that is higher than the host PEO-NaI (⁓ 5 x 10-7 Ω-1cm-1) system by two orders of magnitude. XANES spectra were studied using pristine PEO as a reference. K-edge energy variation of ether oxygen suggests that for low NTP content, salt ions prefer to move through polymer. However, for higher content, the surfaces as well as inner states of NTP crystallites facilitate the ionic conduction. In another approach, incorporation of Na+ ion rich soft organic polymer based electrolyte (e.g. PEO-NaI) between the nano particles of NASICON (Na3Zr2Si2PO12) has been attempted. High ionic conductivity of ⁓ 2 x 10-4 Ω-1cm-1 is achieved at 40oC for the composition of 63NZSP- 37(PEO0.65NaI0.35). Further, XANES and XPS spectra were studied to understand the crowding effect and hence the interaction between Na+ ion and ether oxygen of PEO. K-edge energy of ether oxygen obtained from XANES spectra again suggests that Na+ ions prefer to stay in polymer for low salt content and diffuse through NASICON for high salt content. Preliminary XPS investigations on this system also compliment these findings. Similar trends of XANES spectra were seen for Li+ ion based hybrid polymer electrolytes developed by our group recently [2].

Acknowledgement: This work is supported by UGC-DAE-CSR, Indore, India under collaborative research scheme (CRS) project CSRIC-BL-52/CRS-169/2016-17/833 and DST-SERB project EMR/2015/000275, Govt. of India. The authors are grateful to Dr. Mukul Gupta, Scientist F, UGC-DAE-CSR for support in data analysis and Mr Rakesh Kumar Sah of RRCAT, Indore for SXAS characterization and R. K. Sharma for XPS characterization.

Reference: [1] J. Sun, R.K. Spencer, X. Jiang, R.N. Zuckermann, J. Phys. Chem. B. (2017) 298−305. [2] M.D. Singh, B. Nayak, B. Choudhury, A. Sarit, A. Dalvi, Solid State Ionics. (2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P14: Chemically modified surface-induced graphene oxide for structural consideration

G. Avashthi1, S. S. Maktedar2, M. Singh3 1, 2, 3School of Chemical Sciences, Central University of Gujarat, Gandhinagar-382030, India. Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected]; Contact: Tel: +91-079-23260210; Fax: +91-079-23260076. Indus beamlines Used: SXAS (BL-01), XPES (BL-14), ADXRD (BL-12). The oxidation of graphite to graphite oxide (GtO), holds the oxygen-enriched functionalities over graphene surface. The sonochemical energy is imposed to exfoliate GtO into graphene oxide (GO). The homogenously exfoliated activated GO surface easily can be modified with heteroatoms (N, O and S) doping using sonochemical, microwave or conventional methods. Hence, the sonochemical method has been used to synthesize N-functionalized graphene oxide. The doping of heteroatom on GO surface is studied for synergistic structural transformations as well as diverse applications. The heteroatom probing induces GO surface for understating the chemical modification of various functionalities. The ultrasound assisted activated reactants are easily formed product without using hazardous and toxic chemicals as well as side product formation. In another procedural protocol, the acidic surface of the GO acts as self-catalyst for inducing the reduction in basic medium. The phenol functionalities of natural extracts generate redox potential in the solvation medium. The pH of the medium provides an electromotive force to dissociate phenols into dianions and polyphenols converts into diquinone with releasing of hydride anions. Surface-induced chemical transformation by two electron and two protons play an important role for GO reduction. The structural transformations have been confirmed with SXAS, XPES, XRD, Raman, FTIR, UV, TGA/DTA. The thermal alterations of GO surface confirm the modifications as structural entities. The surface morphology, diffraction pattern and topography have been confirmed by the TEM/SAED, SEM and AFM. Further, the chemically modified GO has been explored for effective photoluminescent, dye degradation, and concentration dependent cell viabilities. The observed PL peaks are due to radiative and non-radiative recombination and associated excess hole electron surface trap state. The cell viabilities have explored with Sulforhodamine B (SRB) assay on MCF-7, HaCaT and Vero cell lines. The significant morphological impact on cell lines confirms Nano- cytocompatible material. Therefore, modified materials can be used as a photosensitive bioscaffold and as catalyst for degradation of industrial toxic chemicals.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P15: Lithium (Li), Magnesium (Mg) and Nickel (Ni) doped ZnO nanostructures for Organic Light Emitting Diodes P. Manzhi1, R. Srivastava2, R. K. Singh2, S. Ojha3, R. J. Chaudhary4, P. Rajput5, and O.P. Sinha1*

1Amity Institute of Nanotechnology, Amity University UP, Sector-125, Noida -201313

2CSIR- National Physical Laboratory, Dr KS Krishnan Marg, New Delhi- 10012

3Inter University Accelerator Centre, Aruna Asaf Ali Marge, New Delhi -110065

4UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore- 452017

5Raja Ramana Centre for Advance Technology, Indore – 452013

Presenting Author email: [email protected];

* Corresponding Author email – [email protected]

Indus Beamline used: IBR/2046/2018-06-11/INDUS-2/BL-9 Scanning EXAFS (29/10/2018- 30/10/2018), IBR/2045/2018-06-11/INDUS-1/BL-2AIPES (20/08/2018-25/08/2018) Li, Mg and Ni doped ZnO and pure ZnO nanostructures have been synthesized by a simple and cost effective wet chemical / hydrothermal method for its potential application in Organic Light Emitting Diodes (OLED). Studies have been undertaken for structural, optical and magnetic properties of ZnO and doped with Li, Mg and Ni ZnO for various concentrations. Field Emission Scanning Electron Microscopy with Energy-dispersive X-ray analysis reveals the morphology and chemical composition of nanostructures and indicated the different structure for ZnO as nanoparticles and with doping it’s converted into the multi facet structure. X-ray diffraction reveals the pure hexagonal phase of the wurtzite structure of ZnO and finds other peaks related to Mg and Ni. UV–Visible suggested the exciton characteristic at room temperature and band gap variation while Photoluminescence spectra reveal two different regions (ultraviolet and blue). X-ray photoelectron spectroscopy studies confirm that the identification of element with their chemical state and effect of doping in ZnO structures. Vibrating sample magnetometer studies showing the magnetic behaviour in the ZnO nanostructures after doping. Extended x-ray absorption fine structure confirms the chemical environment of a Zn element and type of its neighbours after doping, inter-atomic distances and structural disorders in ZnO nanostructures. Synthesized materials have been blended with Poly [9, 9-dioctylfluorenyl-2, 7-diyl] (PFO) and prototype OLED has been fabricated using these materials as an emissive layer. Electroluminescence spectra show prominent blue emission with high intensity and current-voltage curve reveal that the stability of OLED device with doped materials as compared with pristine PFO device.

References: [1] P. Manzhi, M.B. Alam, R. Kumari, R. Krishna, R.K. Singh, R. Srivastava, O.P. Sinha, Vacuum 146, 462- 467 (2017). [2] T.M. Hammad, J.K.. Salem, J. Nanopart. Res. 13, 2205-2212 (2011). [3] S. Fabbiyola, V. Sailaja, L.J. Kennedy, M. Bououdina, J. J. Vijaya, J. Alloys and Com. 694, 522-531(2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P16: Study of thermoelectric Properties of multilayers of Bi2Te3 and Sb2Te3 compounds

V. Swami1, S. Jain1, D. P. Lata1, K. Soni1, D. Sharma1, R. Vyas1, M. Kumari1, Y. K. Vijay1 and Y. C. Sharma1 1Department of Physics, Vivekananda Global University, Jaipur, 303012, India; Presenting authors e-mail: [email protected] Corresponding author: [email protected] INDUS-2 beamlines used: Angle Dispersive X-Ray Diffraction Beamline (BL-12)

In present era there is a need to develop modes and methods for harvesting of waste heat. Telluride compounds are very good thermoelectric materials. They have shown excellent thermoelectric properties around 50°C – 200°C. Studies have shown that their multilayer designs have better thermoelectric properties. In this work we report multilayer thin films of Bi2Te3 and Sb2Te3 compounds of single layer thickness of about 30 – 40 nm which were fabricated using electron beam assisted thermal evaporation on glass and Si substrate. The electrical properties i.e. Hall measurements, carrier concentration, carrier mobility, conductivity have been studied at room temperature. Thermoelectric behavior has been analyzed on the basis of Seebeck coefficient for which our samples show result in coherence to earlier reported values. X-Ray diffraction (XRD) and atomic force microscopy (AFM) and Scanning Electron microscopy (SEM) techniques have been employed to inquire the crystallographic structure and surface morphology of specimen. In-situ ADXRD measurements have also been observed.

Acknowledgement Authors are sincerely thankful to Dr. A. K. Sinha, Dr. M. K. Tiwari and V. Srihari, INDUS-II, RRCAT, Indore for their experimental and technical support.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P17: Quantification of Structural and Electrical lineament of CZTSe thin films

S. Jain1, D. P. Lata1, V. Swami1, K. Soni1, D. Sharma1, R. Vyas1, R. Prajapat1, Y. K. Vijay1 and Y. C. Sharma1 1Department of Physics, Vivekananda Global University, Jaipur, 303012, India; Presenting authors e-mail: [email protected] Corresponding author: [email protected] INDUS-2 beamlines used: Angle Dispersive X-Ray Diffraction Beamline (BL-12)

Solar energy is abundantly available as a renewable energy source; in present scenario there is a huge need to utilize this vast source to quench the side effects of conventional fossil fuels. For the production of solar cells Copper Zinc Tin Selenium (CZTSe) thin films have attracted much attention in recent times due to high natural abundance of constituents, large absorption coefficient and tuneable band gap from 1.0 to 1.5 eV with its non-toxic constituents establishing it environmentally friendly. In this work thin films of Cu2ZnSnSe4 have been prepared by employing RF-DC sputtering method and thermal evaporation method on soda lime glass and Si- wafer substrates with maintaining the substrate temperature of 100º C. Deposited thin films have been annealed further at 200º C and 500º C in air and vacuum. X- Ray diffraction (XRD) and atomic force microscopy (AFM) techniques have been employed to inquire the crystallographic structure and surface morphology of specimen. In-situ ADXRD measurements have been observed from 300º to 500º C which shows that phases start to build up at 450ºC which becomes most prominent at 500ºC The electrical and optical properties were investigated by Hall Effect measurements and UV-VIS spectrophotometer, respectively.

Acknowledgement Authors are sincerely thankful to Dr. A. K. Sinha, Dr. M. K. Tiwari and V. Srihari, INDUS-II, RRCAT, Indore for their experimental and technical support.

References: [1] S. Chen, A. Walsh, Y. Luo, J. H. Yang, X. G. Gong and S. H. Wei, Phys Rev B, 82, 195203, 2010.

[2] W. R. Adhi, L. E. Soo, B. Munir and K. K. Ho, Phys Status solidi A, 204, 9, 2007.

[3] L. Yao, J. Ao, M. J. Jeng, J. Bi, S. Gao and G. Sun, Mater., 9, 241, 2016.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P18: Study of low temperature nitriding of Inconel 600 alloy

D. P. Lata1, R. Kumar2, Y. K. Vijay1 and Y. C. Sharma1 1Department of Physics, Vivekananda Global University, Jaipur, 303012, India; 2Department of Physics, Birla Institute of Technology, Mesra, Jaipur Campus, 302017, India. Corresponding author: [email protected]

INDUS-2 beamlines used: XRF BL-16

The present work reports the findings of low temperature nitriding of Inconel 600 alloy. Improvements in micro-structure and wear analysis of the alloy for nitriding at various temperatures have been investigated. The compositions of nitrided and un-nitrided specimen were investigated by X-ray fluorescence (XRF) and energy dispersive x-ray (EDX) techniques. The XRF spectra confirm the elemental compositions of the specimen which has been maintained at even higher temperatures also. The EDX scanned image of elements presents on the plasma nitrided surface shows that all elements are distributed symmetrical on the surface and the diffusion of nitrogen on the surface of the alloy specimen is uniform. Compositional fractions of various constituents of the alloys obtained from EDX and XRF techniques are in very good agreement. The surface properties have been characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), micro-hardness and wear test methods. In plasma nitriding CrN peak appeared at position of 2θ (37.50) observed only in the samples which were 0 treated at 450 C. The maximum surface micro-hardness ~306HV.025 was observed for these specimen. It was observed from surface morphology images that the crystallite size of grains increased as process temperature increased. It has been observed that nitriding performed at 3500C produces a nitrided layer on the alloy surface which has better wear rate in comparison to the upper temperature treatments.

Acknowledgement Authors are sincerely thankful to Dr. A. K. Sinha, Dr. M. K. Tiwari and V. Srihari, INDUS-II, RRCAT, Indore; Dr. A. K. Bhargav, Professor and Head, Dept. of Metallurgical and Material Science, MNIT, Jaipur, Dr. A. Patnaik, Asso. Prof. Dept. of Mechanical Engineering, MNIT, Jaipur, Dr. G. Raja Ram, Manager, Research & Development at NEI Ltd, Jaipur and Dr. A. K. Srivastava, Asst. Prof. Dept. of Physics, BIT, Mesra, Jaipur Campus for their experimental and technical support.

References: [1] C. Sudha, R. Anand, V. Thomas Paul, S. Saroja and M. Vijayalakshmi, Surf. Coat. Tech., 92, 226, 2013. [2] F. Mindivana and H. Mindivan, Proc. Eng., 68, 730, 2013. [3] R. Kumar, D. Bhardwaj and Y. C. Sharma, J. Mat. Sci., 6(1), 31, 2018. [4] Y. C. Sharma, R. Kumar, V. Vidyasagar and D. Bhardwaj, Mater. Res. Exp., 6, 026559, 2018.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P19: Structural and Microstructural Characterization of an Indian Aurvedic Medicine: Swarn Bindu

D. Sharma1, S. Jain1, D. P. Lata1, V. Swami1, K. Soni1, R. Vyas1, P. P. Vyas2, Y. K. Vijay1 and Y. C. Sharma1 1Department of Physics, Vivekananda Global University, Jaipur, 303012, India; 2Department of Paediatrics, Dr. Sarvepalli Radhakrishnan Rajasthan Ayurved University, Jodhpur, 342037, India Presenting authors e-mail: [email protected], Corresponding author: [email protected]

INDUS-2 beamlines used: X-ray Photo-Electron Spectroscopy Beamline (BL-14)

Man, since its chronological evolution, desire to live long. For which every generation adopts measures in diet and drugs. In Ayurveda Gold has been an ingredient on virtue of its therapeutic properties, mostly used as Swarna Bhasma. This conversion of metallic Gold to medicinal gold (either Swarna Bhasma or Gold compounds; chemical entity of conventional system) is an important part of Ayurveda. In this work structural characterization of Swarn Bhasma, procured from Dabar, India Pvt. Ltd, has been done. The X-ray diffraction (XRD) measurement has been carried out at room temperature. The diffraction peaks indexed with gold ‘Au’ standard (ICDD PDF # 4–0783), respectively for a face centred cubic (FCC) gold material has been observed. In conjunction with a signature of very low intensity diffraction peak which can be attributed to the gold oxide ‘Au2O3’ diffraction peak. XPS study of the Bhasm was carried out at HAXPES beamline (BL- 14), Indus-2, RRCAT. Fig.1 shows (a) the representative survey spectrum of Gold Bhasm (b) Gold 4f xps spectrum of Gold Bhasm. As can be seen, the survey spectrum reveals different gold peaks with silver, carbon and oxygen peaks. The atomic percentages of Gold and Silver were found to be ~95 and ~5% by fitting in casa XPS software (Carbon and Oxygen were not taken into account). Also Gold 4f peaks were fitted and are found in the metallic state (Au 4f7/2 at 84.0 and Au 4f5/2 at 87.7 eV) as can be seen from Fig. 1(b).

Acknowledgement Authors are sincerely thankful to Dr. U. K. Gautam, INDUS-II, RRCAT, Indore for the experimental and technical support.

References: N. Singh and A. Chaudhary, Anand. International Journal of Research in Ayurveda and Pharmacy. 3, 5, 2012.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P20: Band offset measurements in Cr2O3/Ti0.02Cr1.98O3 bilayer thin film using photoelectron spectroscopy

P. Baraskar 1, A. Agrawal1, R. J. Choudhary2, Pratima Sen 1 1School of Physics, Devi Ahilya University, Khandwa road, Indore-452001, India; 2UGC-DAE Consortium for Scientific Research, University Campus, Khandwa road, Indore-452001, India; [email protected]; [email protected]. Indus-1 beamline: 2

The realization of oxide/oxide semiconductor hetrostructure based high performance electronic /optoelectronic/magneto-optical devices warrant the understanding of band alignment at their interface. Herein, we report energy band alignment in pulsed laser ablated Cr2O3/Ti0.02Cr1.98O3 bilayer film from the knowledge of the core level and valence band maxima positions in the corresponding Cr2O3 and Ti0.02Cr1.98O3 single layer films and their respective shifts in Cr2O3/Ti0.02Cr1.98O3 bilayer film. A type II (staggered) band alignment was identified, with the valence band offset and conduction band offset equal to 1.4 eV and -0.8 eV, respectively. This investigation will provide further understanding in the fundamental properties of Cr2O3/Ti0.02Cr1.98O3 heterojunction, which will be useful in the design, modeling and analysis of optoelectronic/magneto-optical devices.

(b) Cr2p3/2 (a) Cr2p3/2 Cr2p1/2 Cr2p 1/2

576.2 eV 576.2

eV 576.6 eV 586.1

586.5 eV 586.5 Intensity(a. u.)

575 580 585 590 595 575 580 585 590 595

Binding Energy (eV) Binding Energy (eV) (c) (d)

VBM =2.6 eV Intensity(a. u.) VBM= 1.1 eV

0.0 0.6 1.2 1.8 2.4 3.0 3.6 0 1 2 3 4 5 6 7 8 Binding Energy (eV) Binding Energy (eV)

Fig1. Cr 2p core level XPS spectra of (a) Cr2O3 (b) Cr2O3/Ti0.02Cr1.98O3 , Valence band Spectra of (c) Cr2O3 and (d) Ti0.02Cr1.98O3.

Acknowledgement: Authors are grateful to Dr. M. Gupt, Dr. U. P. Deshpande from UGC-DAE- CSR, Indore and Mr. A. Wadikar and Mr. S. Karwal for helping in XPS and VBS measurements at RRCAT, Indore. The work was financially supported by UGC-DAE-CSR, Indore (CSR- IC-BL- 61/CRS-178/2018-19/1434, CSR-IC-237/2017-18/1318), Science and Engineering Research Board, Govt. of India, New Delhi (EMR/2016/002500), and UGC SAP-DRS-I, New Delhi (F.530/17/DRS- I2016(SAP-I)), India.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P21: Non-destructive and Label Free Assessment of the Elemental Profile of Foliar by Synchrotron Radiation Induced Energy Dispersive X-Ray Fluorescence Spectroscopy Abhi Sarika Bharti1, Sweta Sharma1, A.K.Singh2, M.K. Tiwari2, and K.N.Uttam3 1 Centre for Environmental Science, Department of Botany, University of Allahabad, Allahabad 2 Synchrotron Utilization Section, Raja Ramanna Centre for Advanced Technology, Indore 3 Saha’s Spectroscopy Laboratory, Department of Physics, University of Allahabad, Allahabad Email: [email protected], [email protected] Indus beamline(s) Used: INDUS-2, Micro X-ray Fluorescence (Beamline-16)

The nutrient profiling of green leafy vegetables is largely concentrated on biochemical assays and their elemental composition is often overlooked. The investigation of elemental composition of plants is essential as they are required in several metabolic processes for the normal growth and development of human body and their deficiency can lead to several clinical disorders. Therefore, the study aims to realize the potential of synchrotron radiation induced energy dispersive X-ray fluorescence spectroscopy technique as a rapid, sensitive and simultaneous multielemental detection tool to investigate the elemental composition of different elements present in some leafy vegetables: dill, fenugreek, mustard and chenopodium. The X-ray fluorescence spectrum of the leaves of dill, fenugreek, mustard and chenopodium are excited by synchrotron X-ray radiation of energy 15 keV and recorded in the energy range <20 keV. The recorded spectrum shows the presence of potassium, calcium, titanium, manganese, iron, nickel, copper, zinc, arsenic and selenium with varying concentration in the different leafy vegetables. The PyMca software has been applied for the calibration free determination of the concentration of the various detected elements. Relative quantitative comparison of the detected elements shows that chenopodium leaves are a rich source of potassium among all the leafy vegetables under study. Leaves of mustard and chenopodium are abundant in calcium while the leaves of dill and fenugreek have higher content of trace elements like manganese, iron, copper, nickel, selenium and zinc. The role of the detected elements has been described in human and plant health.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P22: Prompt screening of the alterations in biochemical and mineral profile of wheat plants stressed with chromium using attenuated total reflectance Fourier transform infrared spectroscopy and X-ray fluorescence excited by synchrotron radiation Sweta Sharma1, A. K. Singh2, M.K. Tiwari2 and K.N.Uttam3 1Department of Botany, University of Allahabad, Allahabad 2Synchrotron Utilization Section, Raja Ramanna Centre for Advanced Technology, Indore 3Saha’s Spectroscopy Laboratory, Department of Physics, University of Allahabad, Allahabad Email: [email protected]; [email protected] Indus beamline(s) Used: INDUS-2, Micro X-ray Fluorescence (Beamline-16)

With mounting pressure of heavy metal pollution on agriculture, the demand of practical tools and protocols for non-destructive, pre-visual detection of plant response towards heavy metals has received great impetus. Advances in modern state of art spectroscopic techniques like synchrotron radiation induced X-ray fluorescence and attenuated total reflectance Fourier transform infrared spectroscopy have the capability of providing a complete picture of the metabolic events taking place in plants stressed with heavy metals without subjecting the sample to pre-processing. Taking this into account, the present study explores the utility of synchrotron radiation induced X-ray fluorescence and attenuated total reflectance Fourier transform infrared spectroscopy along with multivariate analysis for the detection of response in the form of spectral indices of wheat plants towards chromium stress. For this, wheat has been chosen as a model crop plant that has been grown under optimized growth conditions and exposed to chromium at different concentration (0.2, 0.4, 0.6, 0.8 and 1.0 mM). The synchrotron radiation induced X-ray fluorescence spectra of the control and chromium exposed seedlings have been recorded at 10 KeV energy. The analysis of the X-ray fluorescence spectra indicates that exposure of chromium leads to its accumulation in the leaves of the wheat seedlings that result in hampering the uptake of calcium, potassium, manganese iron, copper and zinc by the plants. The alterations in the biochemicals of wheat seedlings as a result of chromium exposure have been assessed by attenuated total reflectance Fourier transform infrared spectroscopy. The infrared spectra have been recorded in the spectral region 4000-400 cm-1 at 4 cm-1 resolution. The observations from infrared measurements reveal that chromium significantly alters the spectral signatures of cellulose, pectin, hemicelluloses, lignin, amide II, amide I and lipid in the leaves of wheat plants and the observed changes are dependent on the dose of chromium. The spectral signatures obtained in this study serve as important monitoring indices for observing the alterations at molecular level in the physiological and metabolic status of plants under heavy metal stress.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P23: Study of electronic properties of CuCo1-xVxO2 using x-ray emission spectroscopy (XPS) and density functional theory

Deepak Upadhyay1, Uttam K. Gautam2, S. N. Jha3, S. R. Kane2, Prafulla K. Jha1 1Department of physics, The M. S University of Baroda Vadodara, 390002, India 2Indus synchrotron radiation division Raja Ramanna Centre for Advanced Technology, Indore- 452013, India 3Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400094, India Presenting Author’s [email protected]; Corresponding Author’s Email: [email protected]

Indus beamline(s) Used: XPS beamline (BL-14) Indus- II

Delafossite-type oxides such as CuMO2 (M = trivalent cation) have considerable potential to be used as renewable energy materials in thermoelectric devices [1], dye-sensitized solar cell (DSSC’s) [2] and catalysts for water splitting [3] because of their layered structure of edge-shared MO6 octahedrons. In this study, the structural and electronic properties of layered ternary delafossite CuCo1-xVxO2 (x=0.2, 0.4, 0.6, 0.8) have been studied using X- ray diffraction (x-ray), x-ray photoemission spectroscopy (XPS). CuCo1-xVxO2 was synthesized by solid state reaction and calcined at 1000 ⁰C for 12 h. The rhombohedral phase with space group R3̅푚 is confirmed by X-ray diffraction analysis. XPS is used to analyse the valence state and oxidation number of components in CuCo1-xVxO2. The survey spectrum shows Cu, Co, and O peaks with reference to the C1s peak at 285.7 eV. The binding energies of Cu (2p3/2) and Cu (2p1/2) are centered at 934.6 and 955 eV respectively. The Co (1s) peak is at 125.2 eV and the O (1s) peak is at 530.5 eV. Significant shift in energy of Co (2p3/2) and Co (2p1/2) is observed in case of vanadium doping at cobalt site. The shift in Co (2p) depicts mixing of p-d hybridization states. To further critically analyse the experimental outcomes, the electronic band structure and density of states (DOS) of CuCo1-xVxO2 have been calculated using density functional theory (DFT).

Reference: 1. Sinnarasa, Y. Thimont, L. Presmanes, A. Barnabé, P. Tailhades, Nanomaterials 7, (2017), 157. 2. M. Yu, G. Natu, Z. Ji, Y. Wu, J. Phys. Chem. Lett. 3, (2012) , 1074. 3. A. K. Diaz-Garcia, T. Lana-Villarreal, R. Gomez, J. Mater. Chem. A, 3, (2015), 19683.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P24: Anomalous magnetic properties of Fe3O4 nanostructures on GaAs substrate probed using X-ray magnetic circular dichroism Gyanendra Panchal, Ritu Rawat, R. J. Choudhary, D. M. Phase UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore-452001, India. Corresponding author: gyanendra.panchal@gmail Indus beamline(s) Used: BL-01 Indus II and BL-02 Indus I, RRCAT

Abstract: Among the various magnetic materials, half metallic ferrimagnetic Fe3O4 with high Curie temperature and low electrical resistivity at room temperature has been at the core of numerous applications and have been studied extensively.1 One-dimensional ferromagnetic nanostructures of Fe3O4 will provide a new component for several electronic, magneto- electronic devices application.2,3 X-ray Magnetic Circular Dichroism (XMCD) is a very powerful technique and it allows to determine the element/site specific magnetism and capable to separate orbital and spin contribution of magnetic moment of different elements. In the present work we have grown Fe3O4 on single crystal GaAs (100) by pulsed laser deposition. We have carried out detailed 700 705 710 715 720 725 730 investigation of electronic and magnetic properties of nanostructures Fe3O4 thin film by synchrotron based VBS and XMCD respectively. VBS and XMCD measurements are performed at BL-01 Indus II and BL-02 Indus I respectively at RRCAT Indore, India4. It turns out that the nanostructures reveal reduced density of states at Fermi level as compared to the 150 nm thick film. Element specific XMCD studies, interestingly, reveals unusually higher magnetic moment and is found to be due to contribution of otherwise quenched orbital magnetic moment also towards the total magnetic moment.

  2 nm Fe O 3 4   XMCD X 0.25   Fig. 1 Room temperature (  )d   r (  )d XANES of at Fe-L edge Background measured at external magnetic field of ±1.2 Tesla q Intensity (Arb. Units) (Arb. Intensity p (shown as σ+ and σ-

700 705 710 715 720 725 730 respectively) and XMCD Photon Energy (eV) spectra of 2 nm Fe3O4 film. References:

1 S.A. Wolf, D.D. Awschalom, R.A. Buhrman, J.M. Daughton, S. von Molnár, M.L. Roukes, A.Y. Chtchelkanova, and D.M. Treger, Science 294, 1488 (2001). 2 S. Aggarwal, A.P. Monga, S.R. Perusse, R. Ramesh, V. Ballarotto, E.D. Williams, B.R. Chalamala, Y. Wei, and R.H. Reuss, Science 287, 2235 (2000). 3 R. Prakash, R.J. Choudhary, L.S. Sharath Chandra, N. Lakshmi, and D.M. Phase, J. Phys. Condens. Matter 19, 486212 (2007). 4 D.M. Phase, M. Gupta, S. Potdar, L. Behera, R. Sah, and A. Gupta, in AIP Conf. Proc. (American Institute of Physics, 2014), pp. 685–686.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P25: Role of heavy metal interface in controlling the structural and magnetic properties of amorphous FeCoB film Jagrati Dwivedi1, Mukul Gupta2, V R Redyy2, Ashutosh Mishra1, V. Srihari3, K. K. Pandey3, Pallavi Pandit4, Ajay Gupta5 1School of Physics, Devi Ahilya University, Khandwa Road, Indore-452001, India 2UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452 001, India 3High Pressure & Synchroton Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India 4Deutsches Elektronen-Synchrotron (DESY), Notkestraße 85, 22607 Hamburg, Germany 5Amity Center for Spintronic Materials, Amity University UP, Sector 125, Noida 201 313, India Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected] Indus beamline Used: Extreme conditions AD/ED-XRD (BL-11) Thin films of FeCoB are the best candidates for magnetic electrodes in MgO based magnetic tunnel junctions. Buffer layer of heavy metals like Mo, has been used to tailor magnetic anisotropy in this system [1]. Post deposition annealing results in crystallization of amorphous FeCoB film into bcc-FeCo phase and plays an important role in enhancing tunnel magnetoresistance [2]. Film having structure; substrate/Mo(30nm)/ FeCoB(x nm)/Mo(2nm) was deposited using Ion beam sputtering (IBS) and dc-magnetron sputtering (dc-MS). The hysteresis loops were taken by magneto-optical Kerr microscope, in UGC- DAE CSR, Indore. GIXRD measurements were carried out at angle dispersive X-ray diffraction station of beamline, BL-11 at INDUS-2, RRCAT, Indore [3]. Effect of Mo buffer layer on the evaluation of magnetic properties of 300Å thick Fe60Co23B17 film with thermal annealing, which deposited using IBS has been studied. The as-deposited film exhibits a uniaxial magnetic anisotropy. With thermal annealing up to 300°C, anisotropy gradually decreases while coercivity exhibits a significant increase. Uniaxial anisotropy reappears after annealing at 400°C. In order to understand the origin of magnetic anisotropy in the film, in-plane and out-plane X-ray diffraction measurements have been done. It is found that with thermal annealing, the film exhibits significant changes in grain texture as well as internal stresses. Variation in grain texture in the film is expected to be the main cause for observed magnetic anisotropy. Similar measurements have been done on 700Å thick Fe43Co40B17 film deposited by dc-MS. As-deposited sample shows uniaxial magnetic anisotropy which is expected behaviour due to the stress generated during deposition. In contrast, MOKE measurement reveals that magnetic anisotropy remained in the film after appearance of bcc-FeCo phase. We find an anomalous magnetization reversal behaviour that occurs for partially disordered, but still anisotropic samples in the vicinity of the HA, at 350°C and 400°C annealed sample. The anomaly of the occurrence of non-uniform magnetization near hard axis can be explained by two-grain Stoner-Wohlfarth model. References

[1] J. Sinha et al., J. Appl. Phys. 117, 043913 (2015).

[2] Y. M. Lee, J. Hayakawa, S. Ikeda, F. Matsukura, and H. Ohno, Appl. Phys. Lett.89, 042506 (2006).

[3] K. K. Pandey, et al., Pramana- J. Phys., Vol. 80, No. 4,670-619 (2013).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P26: Dissection of Catalytic Site in Crucial Gut Microbiome Enzyme: Bile Salt Hydrolase Yashpal Yadava#, Mrityunjay K. Tiwarib#, Deepak Chandac#, ArchanaPundlea#, Sureshkumar Ramasamya#*

aDivision of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune-411008, India,

bPhysical and Material Chemistry Division, CSIR-National Chemical Laboratory, Pune-411008, India cMedical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Hills Road, Cambridge, CB2 0XY, UK #Academy of Scientific and Innovative Research (AcSIR), CSIR-NCL, Pune-411008, India Presenting author Email: [email protected] *Corresponding author Email: [email protected] Indus beamline(s) Used: Indus II PX BL-21

Bile Salt Hydrolases (BSHs) are enzymes that catalyze the hydrolysis of Bile Acids and consequently promote the reduction of cholesterol level in the mammalian body (1). Out of several reported BSHs, the Enterococcus faecalis BSH (EfBSH) has been reported to have the highest enzymatic activity (2). Herein, we have investigated the mechanistic details of the EfBSH activity. The study was carried out employing two mutants of EfBSH: E269A and R207A, which shows differential catalytic activity. The mutant E269A exhibits significant loss in the BSH activity with an increased affinity towards the substrate, whereas R207A was found to be involved in allostery with an increased EfBSH activity towards tauro-conjugated bile acids. The structural and electrostatic force analyses of the active sites of the E269A mutant and the wild type EfBSH (wt EfBSH) revealed that the interaction between Glu21 and Arg207 is the determining factor in maintaining the dynamic allostery and high activity of EfBSH.

YY thanks University Grant Commission (UGC) for the Senior Research Fellowship and beam line scientists of PX-BL21, INDUS-II, RRCAT, for helping in X-ray data collection. References:

1. Begley, M., Hill, C., & Gahan, C. G. M. Applied and Environmental Microbiology, 72(3), 1729–38 (2006). 2. Chand, D., Ramasamy, S., & Suresh, C. G. Process Biochemistry, 51(2), 263–269 (2016).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P27: Magnetic field dependent dielectric and magnetic field sensitivity behavior of Zn0.95Fe0.05O Priyanka Singh and Brajendra Singh* Materials Chemistry Lab, Centre of Material Sciences, University of Allahabad Allahabad 211002, Uttar Pradesh, India. *E-mail: [email protected]; [email protected] Indus beamline(s) Used: SXAS beamline (BL-01) of the INDUS 2

ZnO is a potential candidate for scientific and technological perspectives for multipurpose applications due to its distinctive properties like high optical transmittivity, electron mobility, large electromechanical coupling and good charge carrier transport properties [1-2]. The sensing mechanism depends mainly on giant magneto-resistance, superconducting quantum interference phenomenon and magneto-electric effects [3]. Magneto-electric properties of doped ZnO can be used in transparent device, which may be facilitated for magnetic sensing, gas sensing, and less expensive transparent conducting glass for display and photovoltaic panels. Fe doped ZnO shows quick response, high sensitivity, excellent selectivity and long-term stability for gas sensors [4]. Fe is known for its variable valence states, and it may have mixed valence states (Fe+2, Fe+3) when successfully substituted at a Zn site in ZnO [5-6]. In this study, we have explored the structural, electronic and magnetic field dependent properties of Zn0.95Fe0.05O, was synthesized by microwave-assisted combustion method. The x-ray diffraction (XRD) pattern of Zn0.95Fe0.05O shows the successful substitution of Fe at Zn site in ZnO and shows the shift in peaks towards lower theta values of Zn0.95Fe0.05O in comparison to the XRD pattern of ZnO. Mixed valence states of Fe (Fe+2 and Fe+3) shown by the Soft x-ray absorption spectroscopy (SXAS) studies. Magnetic Field dependent dielectric properties of Zn0.95Fe0.05O shows the change in comparison to ZnO from low to high frequency. The dielectric constant εr is found to be 2.88*105 in 1 Hz and 10.37 in 1 MHz frequency in the 500 Gauss magnetic field for Zn0.95Fe0.05O. Magnetic field sensitivity is found as ~ 16% in the 15 kG magnetic field with 30 MHz frequency for Zn0.95Fe0.05O [7].

Priyanka Singh thanks the UGC-DAE-Consortium for Scientific Research (CSR), Indore Centre, for providing financial support under the CRS project scheme. B. Singh thanks Dr. Mukul Gupta for his help in collecting SXAS data and Dr. R.J. Choudhary for magnetic measurement.

References [1] L. Schmidt-Mende and J.L. Macmanus-Driscoll, Mater.Today 10, 40 (2007). [2] D.C. Look, Mater. Sci. Eng. B 80, 383 (2001). [3] M. Phan,and H. Peng, Prog. Mater. Sci. 53, 323 (2008). [4] Ling Zhu, Wen Zeng, Sensors and Actuators A, 267 (2017). [5] D. Karmakar, S.K. Mandal, R.M. Kadam, P.L. Paulose,A.K. Rajarajan, T.K. Nath, A.K. Das, I. Dasgupta, and G.P.Das, Phys. Rev. B 75, 144404 (2007). [6] A. Singhal, S.N. Achary, A.K. Tyagi, P.K. Manna, and S.M.Yusuf, Mater. Sci. Eng. B 153, 47 (2008). [7] B.Singh, A. Tandon, P.Singh and Anand K. Pandey, J. Electron. Mater. 47,12 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P28: Element-Specific Magnetic Properties of Fe4N Films Probed by X-ray Magnetic Circular Dichroism Nidhi Pandey1, Mukul Gupta1*, D. M. phase1 and S. Pütter2

1UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India

2 Jülich Centre for Neutron Science (JCNS) at Heinz Maier-Leibnitz Zentrum (MLZ) Forschungszentrum Jülich GmbH, Lichtenbergstr. 1, 85747 Garching, Germany Presenting Author’s Email:[email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: Soft X-ray absorption spectroscopy (SXAS) beamline (BL-1)

Abstract: Element-specific magnetic properties of epitaxial Fe4N thin films were probed by the circular dichroism in x-ray absorption spectroscopy (XMCD). Epitaxial Fe4N thin films were grown by three different techniques, direct current magnetron sputtering (dcMS), molecular beam epitaxy (MBE) and high power impulse magnetron sputtering (HiPIMS). XMCD measurements were performed at the nitrogen K and at the Fe LIII and LII absorption edges shown in fig 1. Applying the sum rule, values of magnetic moments were evaluated and found to be highest for the HiPIMS grown Fe4N sample. A small difference in the intensity of µ+ and µ- can also be seen at the N edge for HiPIMS grown sample (shown in fig 1), indicated the possible polarization of N in the Fe4N sample. In addition, here it is also interesting to see that the µ+ and µ- intensities get reversed compared to Fe L edges. These XMCD results confirm the existence of negative (small) magnetic moment of N in Fe4N. The origin of such magnetic moment at N atom is theoretically explained in terms of the extension of spin-down electron wave function near the interstitial region using spin-density plot located within the muffin-tin spheres.

X-ray absorption spectroscopy (XAS) spectra collected at Fe LIII and LII and N K edges revealed the local electronic structure of Fe4N. The shoulders (shown by ‘a’ in fig 1 (A)) signify the interaction between the site specific Fe and N which is caused by the local electronic structure of the Fe atoms at II sites. Similarly, at N K edge, the line spectral shape can also be explained by the dipole transition from the N 1s core-level to the hybridization state formed by π* and σ* anti-bondings[2]. This hybridization plays an important role in featuring the electronic structures and physical properties of Fe4N.

Fig 1: XAS and XMCD spectra taken at Fe L (A), and N k edges (B) of Fe4N thin films. References:

[1] D. M. Phase, M. Gupta, et. al., AIP Confer. Proceed. 1591, 685 (2014). [2] K. Ito, et. al., Appl. Phy. L. 98, 102507 (2011). 69

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P29: Role of spin-lattice coupling in mediating exotic properties in Brownmillerites G. Sharma1, S. Tyagi1, V. Sathe1 1UGC-DAE Consortium for Scientific Research, Indore, 452001, India. Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: SXAS (BL01), ADXRD (BL12) Functional oxides are recently been highly investigated due to their potential applications. Multiferroics and materials showing magnetodielectric effects are anticipated to be the materials of the near future. Similarly, oxides that show negative thermal expansion (NTE) are also finding technological applications. However, most of the applications demand strong coupling among various degrees of freedom at and around room temperature. Brownmillerites provide such an opportunity as these compounds show magnetic order around room temperature. Recently, these compounds are being investigated because of properties, such as magneto-dielectric effect, Spin Reorientation transition, spin-lattice coupling etc. The interesting physics of Brownmillerites has opened a plethora of applications.

We have investigated the Brownmillerite compound Ca2FeAlO5 (TN ~70C) in polycrystalline form for the coupling among various degrees of freedom at and around room temperature. Temperature dependent synchrotron x-ray diffraction (SXRD), room temperature x-ray absorption spectroscopy, Raman spectroscopy and Mossbauer Spectroscopy with temperature dependent thermal expansion measurements were carried out on this compound [1,2]. We have observed anomalous thermal expansion behavior in the thermal expansion measurements which was supported by our temperature dependent SXRD studies. The Raman and SXRD studies showed existence of strong spin-lattice coupling in this compound. The thermal expansion coefficient calculated from SXRD and strain gauge studies resulted in a negative thermal expansion (NTE) with β ≅ -6.41 x 10-5 °C-1 from room temperature up to ~70 °C making it very attractive for industrial applications.

Another material in this category is Ca2FeCoO5 which has shown interesting magnetic and magneto dielectric properties in our studies. The compound has been studied by temperature dependent Mossbauer spectroscopy, Raman spectroscopy, SXPD, temperature and field dependent complex dielectric spectroscopy. Temperature dependent SXPD and Raman spectroscopy and Mossbauer spectroscopy studies indicated towards the presence of strong spin lattice coupling around the spin reorientation transition (SRT) at ~220K. The sample also exhibited giant magnetodielectricity around the SRT. The role of spin-lattice coupling in mediating this giant magnetodielectricity was elucidated [3]. The authors would like to acknowledge, Dr. V. R. Reddy, Dr. R. Rawat, Dr. N. P. Lalla, Dr. A. M. awasthi, Dr. R. J. Choudhary, Dr. D. K. Shukla and Dr. D. M. Phase from UGC-DAE, CSR for their help in various experiments. Dr. A. K. Sinha and Dr. Archana Sagdeo (RRCAT) are acknowledged for their support in the SXRD measurements at BL12 Indus II synchrotron source, RRCAT.

References [1] G. Sharma, D. Kumar, S. Tyagi, V. R. Reddy, R. Rawat, A. K. Sinha, N.P. Lalla and V. Sathe, J. Alloy Compd. 732, 358 (2018). [2] G. Sharma, V. Sathe, S. Tyagi, R. J. Choudhary, S. D. Kaushik and V. Siruguri, Ceram. Int. 44, 1986619871 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P30: Photon Source: A Versatile Tool to Elucidate Physical Properties of Strain Treated Ferroic Oxide Materials S. Tyagi and V. G. Sathe

1UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India Presenting Author’s Email: [email protected]; Presenting Author’s Email: [email protected] Indus beamline(s) Used: (EC-AD/EDXRD (BL-11); SXAS (BL-01); AIPES Transition metal based ferroic (ferroelectric, anti-ferroelectric, ferromagnetic, anti- ferromagnetic, multiferroic etc.) oxides perovskite are getting wide attention from the applied scientific community for its unique applications such as electrodes, sensors, recording media, GMR, TMR etc. It is by now widely accepted in literature that introduction of the strain (externally or internally) in the system produces large variation in its physical properties and opens new dimension for utilization of the materials. Our aim is to investigate and sketch the extraordinary spectrum of the physical properties of the strain treated oxide materials using the synchrotron photon sources. In one of our report, we observed strong spin-orbit coupling that is a cause for enhanced magnetic moment in epitaxial SrRuO3 thin films. Enhanced magnetic moment and coercivity in SrRuO3 thin films are significant issues for advanced technological usages and hence are researched extensively in recent times. Most of the previous reports on thin films attributed the high spin state for the observed enhanced magnetic moment. Contrary to that, in our studies the Ru ions are found to be in low spin state and the orbital moment is shown to be contributing significantly in the enhancement of magnetic moment in our epitaxial thin films that possessed strain disorder. To probe the spin state and orbital contributions, we employed x-ray absorption spectroscopy and resonant valance band spectroscopy on these films at BL-01 beamline of Indus-2 and AIPES beamline of Indus-1 synchrotron source at Raja Ramanna Centre for Advanced Technology (RRCAT), India. The existence of strong spin-orbit coupling responsible for the de-quenching of the 4d orbitals is confirmed by the observation of the non- statistical large branching ratio at the Ru M2,3 absorption edges. In another report, we utilized other aspect of the synchrotron source and studied x-ray diffraction measurements on well-characterized powder samples of BaTiO3 and SmFeO3 under pressure (0–40 GPa). The pressure dependent X-ray diffraction studies on BaTiO3 provided estimation of the rate of change of volume as a function of pressure resulting in bulk modulus of 215±9 GPa. The electron density plots for SmFeO3 is obtained from the pressure dependent x-ray diffraction that provided a direct visualization of the deformation at the Fe- site, while the environment at the Sm site showed there is more symmetric structure. Moreover, the variation in the FeO6 octahedral tilt at high pressures resulted in large variations in the phonon spectra at the respective pressures indicating modification in local symmetry leading to changes in magnetic structure. We would like to acknowledge Velaga Srihari, Himanshu Kumar Poswal, Deodatta M. Phase, Ram J. Choudhary and Mukul Gupta for their support in the measurements at the INDUS-2 and INDUS-1, RRCAT, Indore, India. 71

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P31: Temperature dependent XRD study of magneto-elastic coupling in

four-layer Aurivillius compound Bi5FeTi3O15

Deepak Prajapat1, V. Raghavendra Reddy1, Archana Sagdeo2, A. K. Sinha2

1UGC DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore, India

2Indus synchrotron utilization division, RRCAT, Indore, India.

Presenting author’s email: [email protected] Corresponding author’s email: [email protected] Indus beamline used: Angle dispersive XRD (BL 12) 2- Aurivillius compounds consist of m perovskite layers (Am-1BmO3m+1) stacked periodically and 2+ separated by fluorite-like (Bi2O2) layers. Four layer Aurivillius compound Bi5FeTi3O15 (BFTO) is considered as the combination of ferroelectric Bi4Ti3O12 and magnetic BiFeO3 stacked together and therefore are considered to be potential candidates for the multiferroic behaviour. The single phase Bi5FeTi3O15 is paramagnetic down to lowest temperature (2 K). Recently first principle calculations have shown that long range magnetic ordering can by induced in these compounds by the substitution of the penta-valent non-magnetic cations at the B site in these compounds [1]. In the present work we have prepared series of V5+ substituted BFTO samples and observed the development of anti-ferromagnetic ordering. Temperature dependent XRD measurements are carried out on selected samples at BL-12 beamline of Indus-2. Figure-1 shows the representative XRD data of 50% V5+ substituted BFTO. The data indicates no structural change down to 50 K. However considerable change in the unit cell volume is observed across TN indicating the role of magneto-elastic coupling.

Fig1. Temperature dependent XRD pattern Fig2. Temperature dependent unit cell

of Bi5Fe1.5Ti2V0.5O15 volume and chi Inverse of the Bi5Fe1.5Ti2V0.5O15

References: [1] Axiel Yael Birenbaum et al., Physical Review B 95, 104419 (2017).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P32: Weak negative thermal expansion (NTE) in relaxor ferrolectric BaTi0.7Sn0.3O3 Akash Surampalli1, Anjali Panchwanee1, V. Raghavendra Reddy1, Archana Sagdeo2 and A. K. Sinha2

1UGC DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore, India

2Indus synchrotron utilization division, RRCAT, Indore, India.

Presenting author’s email: [email protected] Corresponding author’s email: [email protected] Indus beamline used: Angle dispersive XRD (BL 12)

Relaxors which are characterized by dispersion in their broad dielectric maxima peak and no macroscopic structural change across the dielectric transition has gained attention due to its scope in designing piezo-electric, electro-caloric devices etc., that can work in a broad temperature range. The existence of such dielectric and polarization properties over a wide range of temperatures are attributed to the existence of Polar Nano Regions (PNR’s). From the time of its experimental evidence, the origin and dynamics of PNR’s is still controversial [1].

In the present work we explore the average structural properties of relaxor BaTi0.7Sn0.3O3 in the region of dielectric maxima via X-ray diffraction technique. We observed a weak negative thermal expansion (NTE) in the region of dielectric maximum extending to the lower temperatures. In pure ferroelectrics NTE is observed around Curie temperature where the onset of polarization drives the NTE [1]. Hence, the observed weak NTE in the present work is interpreted similar to that of pure ferroelectrics considering that there’s an onset of local static polarization at temperature T* (local Curie temperature).

300 K Data Fit * Difference T Bragg Position 66.24 2.00

DielectricConst (10

1.75 )

3 66.22 10 15 20 25 30 35 1.50

50 K Volume(A

Intensity (a. u.) (a. Intensity 66.20 1.25

3

)

1.00

66.18 100 200 300 10 15 20 25 30 35 Temperature (K) 2 (Degree) Figure 1: Representative XRD patterns of Figure 2: Variation of Unit cell Volume and dielectric BaTi0.7Sn0.3O3 at the indicated temperatures constant of BaTi0.7Sn0.3O3 with temperature

1 B. Dkhil, P. Gemeiner, L. Bellaiche, E. Dul, E. Mojaev, and M. Roth, Phys. Rev. B. 80, 064103 (2009)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P33: Evidence of magnetoelastic coupling in -Mn2O3 Mohit Chandra1, Satish Yadav1, R. J. Choudhary1, R. Rawat1, A. K. Sinha2, MarieBernadette Lepetit3,4 and Kiran Singh1, * 1UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore - 452001, India 2 HXAL, Synchrotrons Utilization Section, RRCAT, Indore 452013, India 3 Institut Néel, CNRS UPR 2940, 25 av. des Martyrs, 38042 Grenoble, France 4 Institut Laue Langevin, 72 av. des Martyrs, 38042 Grenoble, France [email protected], [email protected] Indus beamline Used: Indus-2 (BL-12)

The polycrystalline sample of α-Mn2O3 was prepared through standard solid state reaction method. The purity of the sample was confirming through x-ray diffraction (XRD) measurement as well as by using the synchrotron powder x-ray diffraction (SXRD) measurement. Magnetically it shows two antiferromagnetic transition one around 80 K and the other at 25 K. Earlier the crystal structure of - Mn2O3 was thought to be cubic with space group Ia-3 at RT [1], latter by Geller et al. [2], found the crystal structure is orthorhombic with space group Pcab (distorted from the cubic structure) and have a cubic to orthorhombic transition around 308 K. As the distortion is very small and the XRD data are equally fitted using both the space group and difficult to conclude conclusively the correct crystal

structure of α-Mn2O3 at RT. We have performed SXRD at Indus-2, BL-12 and found a significant change in RT data. In addition, we found the presence of (034) peak which is not allowed in Ia-3 and confirm the orthorhombic structure of Mn2O3 at RT [3]. The temperature dependent SXRD shows the splitting in peaks (800) and (811) at higher 2θ value near magnetic transition. The detailed temperature dependent SXRD measurements across magnetic ordering temperature show a significant change in lattice parameter and unit cell volume. Our results clearly evident the presence of

Fig. 1 RT XRD and temperature dependent magnetic susceptibility then the splitting of (800) and (811) peak at selective temperature and the last one the temperature dependent lattice parameters and b/c ratio and unit cell volume. Acknowledgements: The authors (MC, SY and KS) are very much thankful to Dr. Archana Sagdeo and Mr. M. N. Singh for their help during low temperature SXRD measurements. *Presently at Department of Physics, Dr. B.R. Ambedkar National Institute of Technology, Jalandhar, India. References [1] L. Pauling and M. D. Shappell, Z. Kristallogr. 75, 128 (1930) [2] S. Geller, J. A. Cape, R. W. Grant, and G. P. Espinosa, Phys. Lett. A 24, 369 (1967). [3] M. Chandra, S.Yadav, R. J. Choudhary, R. Rawat, A. K. Sinha, M. B. Lepetit, and K. Singh, Phys. Rev. B 98, 104427 (2018).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

+ P34: Nanopatterning on Si (100) using N2 molecular ion beam Khushboo Bukharia1,2 Dipak Bhowmik, Prassanta Karmakar2, Pallavi Pandit3, S. V. Roth3, Mukul Gupta4, Ajay Gupta1

1Amity Centre for Spintronics Materials, Amity University, Noida 201313, India 2Veriable Energy Cyclotron Centre, 1/AF, Bidhannagar, Kolkata 700064, India 3P-03 PETRA III, DESY Photon Science, Hamburg, Germany 4UDC-DAE Consortium of scientific research, Khandwa road, Indore 452001, India Email:[email protected] ; [email protected] Indus Beamline used- SXAS Beamline BL-01, EXAFS Beamline BL-09, EDXRD Beamline BL-11

+ Nanopatterns on silicon substrate were produced by low energy ion beam. For this N2 molecular ion beam is used. Generally inert gas like argon or xenon is used as ion to be bombarded on substrate because of its non-reactive nature and heavier mass but it has been + reported that Nano patterns are well formed with N2 atoms as compared to Argon ion. SixNy and SiO2 are formed with the initial ion bombardment. It is suggested that the change in chemical composition leads to non-uniform sputtering yield of the sample surface which results in perturbation and consequent quick ripple structure formation [1]. The irradiation of 5 keV + o N2 molecular ion beam on Si (100) sample at 60 was carried out by ECR Ion Source at VECC, Kolkata. The fluence was varied from 2x10 15 atoms/cm 2 to 7x10 17 atoms/cm2. Post irradiation, the surface morphology of the implanted samples was examined by Atomic Force Microscopy (AFM) (Nanoscope IV digital instrument) in contact mode and the data is analysed by WSxM code [2]. Grazing Incidence Small Angle X-Ray Scattering (GISAXS) was done at DESY PETRA III Germany at the energy of 13keV and data is analysed by Dpdak [3]. XRR and SXAS were performed at UGC-DAE-CSR, Indore and BL-01, RRCAT, Indore Respectively.

+ We found that the ripples formed by N2 molecular ion beam are self-organized and uniform. We can conclude that the roughness increase linearly with fluence whereas the wavelength remains almost constant. GISAXS plots show the evolving asymmetry in the side bands as the fluence increases. One can see that the intensity of left and right side bands is asymmetric. This suggests that ripples have a sawtooth shape. The asymmetry increases with increasing fluence. XRR plot suggests that nitride layer of approx. 15 Å is formed at the lowest fluence which increases as the fluence is increased. Additionally, Nitride phase of Silicon has been characterized by Soft X-ray Absorption Spectroscopy.

References-

[1]. S. Bhattarjee, P. Karmakar, A. Chakrabarti, Nucl. Instr. Meth. B 278 (2012) 58

[2] I. Horcas, Rev. Sci. Instrum 78, 013705 (2007)

[3] G. Benecke, http s://dpdak.desy.de/index.php/Hauptseite(2013)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P35: Estimation of gain of GEM detector geometry made in GMSH by using Garfield++

A. S. Lihitkar1, U. A. Palikundwar1

1RTM Nagpur University, Nagpur, 440033, India;

Email:[email protected]; [email protected]

Indus beamline Used: Indus-2 Beamline-07

A gaseous ionization detector with Gas Electron Multiplier (GEM) is used in various applications for radiation detection (e.g. COMPASS experiment, CMS) at CERN. Because of its excellent spatial and time resolution it has a potential to be used in sensitive detection of X-rays. These GEM based detectors, thus, offer broad applications in many diverse fields such as medical diagnostic imaging, X-ray spectroscopic and diffraction techniques, industrial and non-destructive testing. A standard GEM is a both side copper coated kapton dielectric sheet mostly with a double conical shape holes. The recent studies suggested that cylindrical shape holes may be advantageous. We are working on fabrication of GEM sheets with cylindrical shape holes using X-ray lithographic technique. Efforts are also made to test different materials instead of kapton for GEM sheets. It is very important before going into actual fabrication of GEM sheets to have an estimate of different properties that may ease the process and for the optimisation of functioning of the detector. Generally, a particle simulation software Garfield++ is used for the characterisation of GEM detectors. Garfield++ cannot implement complex geometries and requires an electric field generated externally. It is used to simulate the electron avalanche and to estimate the gain. Using Garfield++, GEM detectors were optimised for design parameters like, hole diameter, pitch and various potential difference to get the best fitted configuration of final assembly. The present work includes the use of GMSH, a CAD based software, for designing a cell of GEM detector and Elmer, a finite element software, for creating a field map. The field map also visualised by ParaView, a data analysis and visualisation software. We obtained gain of GEM detector for varying potential applied at the metal surface of GEM. We acknowledges UGC-DAE Consortium for Scientific Research (CSR), Indore, India for the financial support, reference number CSR-IC-BL-72/CRS-189/2016-17/853. We also thankful to the Indus-2, Raja Ramanna Centre for Advance Technology (RRCAT), Indore, India for X- ray lithography support on beamline BL-07 X-Ray Lithography.

References [1] J. Benlloch, IEEE Tran. on Nucl Sci., 45(3), 234–243. (1998).

[2] A. Sharma, Nucl. Instr. and Meth. A 454, 267-271 (2000).

[3] C. Shalem, Nucl. Instr. and Meth. A 558(2), 475–489 (2006).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P36: Study of magnetic and structural properties of Fe nanoparticles in MgO matrix

Pramod Vishwakarma1, P. Rajput2, S.N. Jha2, H.-C. Wille3, Ajay Gupta1,*

1Amity Centre for Spintronic Materials, Amity University UP, Sector 125, Noida 201 313 2Raja Ramanna Centre for Advanced Technology, Indore-452013, India 3Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany Presenting Author’s Email:[email protected]; *Corresponding Author’s Email: [email protected] Indus beamline(s) Used: BL-09 Embedded magnetic nanoparticles are very intense research topic due to their application capability in multidisciplinary fields in present and future technology like non-volatile magnetic memory [1], high density magnetic storage media [2], magnetic recording heads [3], magnetic resonance imaging [4]. Especially, nanoparticles exhibiting an epitaxial relation with respect to the host matrix are of primary interest for data storage, since a fixed orientation with respect to feasible read and write head is required [5]. In the present work we are studying magnetic properties of Fe nanoparticles in MgO matrix using MOKE (Magneto-optic Kerr effect) and NFS (Nuclear Forward Scattering) measurements and for structural properties Extended X-Ray Absorption Fine Structure (EXAFS) has been used. A wedge-shaped film of Fe was sandwiched between two layers of MgO film. By MOKE measurements 0.16 nm thick magnetic dead layer has been detected at one interface. NFS measurement has confirmed that initially Fe film is nonmagnetic either due to superparamagnetic behaviour or oxidation of the magnetic material. EXAFS study has confirmed that initially Fe interacted with oxygen and formed oxide. .

(a) (b)

(c)

Kerr Signal (arb.units)

0 1 2 3 4 5 Thickness (nm) Figure 1. (a) Sample structure (b) Intensity of Kerr signal as a function of the thickness of iron film (c) Iron XAFS pattern References

[1] S. Tehrani, E. Chen,M. Durlam et al., Journal of Applied Physics, 85, 8 (1999). [2] T. Thomson, G. Hu, and B. D. Terris Physical Review Letters, 96, 25 ( 2006). [3] J. R. Childress and R. E. Fontana Jr. Comptes Rendus Physique, 6, 9 (2005). [4] S.H. Chung,A.Hoffmann, S.D. Bader et al Applied Physics Letters, 85, 14 (2004). [5] J. P. Wang, Nat. Mater. 4, 191 (2005).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P37: Interface Sharpening in Miscible and Isotopic Multilayers: Role of Short-Circuit Diffusion A. Tiwari1, M. K. Tiwari2, Mukul Gupta3, H.-C. Wille4 and A. Gupta1* 1Amity Centre for Spintronic Materials, Amity University, U.P, Sector 125, NOIDA 201313, India 2Raja Ramanna Centre for Advanced Technology, Indore-452013, India 3UGC-DAE, Consortium for Scientific Research, Indore-452017, India 4Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany [email protected], *[email protected]

Indus beamline(s) Used: BL-16 XRF Microprobe, Indus-2 In the present work, taking Cu/Ni as a model system, a general phenomenon is reported which results in sharpening of interfaces upon thermal annealing, even in miscible systems. Anomalous x-ray reflectivity from a Cu/Ni multilayer has been used to study the evolution of interfaces with thermal annealing. Annealing at 423 K results in sharpening of interfaces by about 38%. The effect is very general in nature, and is different from the one reported in the literature, which requires a large asymmetry in the diffusivities of the two constituents. General nature of the effect is conclusively demonstrated using isotopic multilayers of 57Fe/naturalFe, in which evolution of isotopic interfaces has been observed using nuclear resonance reflectivity. It is found that annealing at suitably low temperature (e.g. 523 K) results in sharpening of the isotopic interfaces. Since chemically it is a single Fe layer, any effect associated with concentration dependent diffusivity can be ruled out. The results can be understood in terms of fast diffusion along short-circuit paths like triple junctions, which results in an effective sharpening of the interfaces at relatively low temperatures.

(b) 1.0 100 Pristine 423K_0.5h

4

z 423 K_1h 473 K_1h

Rxq 523 K_1h 0.8

-3 10 1.2 1.4 -1 0.6

q (nm ) %) Fe (atomic z 0

10 Pristine 57

0.4 10-2

x-ray reflectivity x-ray

0.2 623 K 423 K_0.5h 573 K 10-4 523 K

0.0 Pristine Concentration of Concentration

0.5 1.0 1.5 2.0 2.5 3.0 0 1 2 3 4 5 6 -1 q (nm ) Thickness (nm) z X-ray reflectivity of Cu/Ni multilayer Concentration profiles as obtained from the annealed at 423 K for 0.5 h. Inset best fit of the nuclear resonance reflectivity compares the reflectivity at the Bragg data of the isotopic multilayer of peak of samples annealed at different 57Fe/naturalFe, showing interface sharpening at temperatures. 523 K.

References:

[1] Z. Erdélyi, M. Sladecek, L. M. Stadler, I. Zizak, G. A. Langer, M. Kis-Varga, D. L. Beke, and B. Sepiol, Science 306, 1913 (2004). [2] Z. Erdélyi, I. A. Szabó, and D. L. Beke, Phys. Rev. Lett. 89, 165901 (2002).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P38: Magnetically retrievable Ce doped Fe3O4 nanoparticles: Electronic structure Analysis Aashima1, Shivani Uppal1, Arushi Arora1, Sanjeev Gautam2, Suman Singh3, R.J. Choudhary4, S.K. Mehta*1

1Department of Chemistry and Centre of Advanced Studies in Chemistry, Panjab University, Chandigarh 160014, India 2Dr S. S. Bhatnagar University Institute of Chemical Engineering and Technology (SSB UICET), Panjab University, Chandigarh, 160014, India 3CSIR – Central Scientific Instruments Organization, Sector-30, Chandigarh 160030, India 4UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore – 452 017, India Email: [email protected] 1 In view of the significant impact of magnetically retrievable nanostructures , Fe3O4 and Ce- doped Fe3O4 nanoparticles were synthesized via hydrothermal route and employed as scaffolds for the removal of Reactive black 5 (RB5), azo dye. Fabricated nanoparticles with varying amount of cerium concentrations (1.5-3.5%) were characterized using basic techniques like FTIR, XRD analysis etc. Fe3O4 displayed better Ms than the doped nanoparticles due to the presence of surface defects. The observed disorder causes a decrease in the exchange coupling between neighbouring iron ions at the surface. The retention of magnetic behaviour even after cerium amalgamation was demonstrated and confirmed from VSM studies. XPS was recorded to evaluate the elemental composition, chemical environment and oxidation states of the elements present in nanoparticles. The tropical behaviour of the magnetic nanoparticles was investigated by BET analysis which reveals the mesoporous structure of the prepared samples. A comparison of the local electronic structure around the Ce site with that around the Fe site indicates that there is formation of cerium oxide and magnetite. The oxygen K-edge spectra that originated from the hybridization between cerium 4f and oxygen 2p states are sensitive to the oxidation state and depend strongly on the concentration of metal. The Ce M4,5-edges and 2 the Fe L2,3-edges reveal the variations of the charge states of Ce and Fe upon doping , respectively. The magnetic absorbents could rapidly be separated from wastewater with an external magnetic field after adsorption.

References [1] J. Gong, B. Wang, G. Zeng, C. Yang, C. Niu and Q. Niu, J. of Hazard. Mat., 2009, 164, 1517– 1522. [2] N. J. Lawrence, J. R. Brewer, L. Wang, T.-S. Wu, J. Wells- Kingsbury, M. M. Ihrig, G.Wang, Y.-L. Soo, W.-N. Mei and C. L. Cheung, Nano Lett., 2011, 11, 2666–2671.

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P39: Role of Co/Cu-implantation in barrier layer MgO films in MTJ: XAS study Baljeet Kaur1, Richa Bhardwaj1, K. Asokan3, R.J. Choudhary4, Parasmani Rajput5, S.N. Jha5, Navdeep Goyal1 and Sanjeev Gautam2 1Department of Physics, Panjab University, Chandigarh - 160 014, India. 2 Dr. S.S. Bhatnagar University Institute of Chemical Engineering & Technology, PU, Chd - 160 014, India. 3 Materials Science Division, Inter-University Accelerator Centre, New Delhi – 110067, India. 4 UGC-DAE Consortium for Scientific Research, Indore 452001, India. 5 Atomic & Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400094, India. Presenting author’s email:[email protected]; Corresponding author’s email: [email protected]

In present work, Co and Cu ions are selected for the implantation on MgO thin films grown on Sisubstrate by Radio frequency (RF) sputtering. Low Energy Ion Beam Facility (LEIBF) available at Inter-University Accelerator Centre (IUAC), New Delhi, India is used for the implantation process at low energy of 100 KeV and three fluences of 1 ×1016, 2.5 × 1016 and 5 × 1016 ions/cm2 are chosen for ion implantation. X-ray Absorption Spectroscopy (XAS) measurements were done at beamline BL09 in Indus-II, RRCAT, Indore and the magnetic properties were studied using SQUID magnetometer at Room Temperature (RT) in UGC- DAE, Indore. Magnetism without d-orbital electrons seems to be unrealistic; however, observed magnetism in non-magnetic oxide MgO have opened new avenues in the field of magnetism. This magnetism is believed to occur due to polarization induced p-orbitals. The presence of vacancies at the surface and subsurface also affects the magnetic behavior of these oxides. Moreover, oxygen vacancies associated with misfit stress at the film substrate interface in MgO thin films are responsible for room temperature ferromagnetism (RTFM) [1]. In figure, from XANES spectra it can be seen that ion implanted MgO thins films show +2 valence state of the Co and Cu ions in host MgO [2]. Whereas in MH loop, implantation of Co in MgO film gives the highest saturation magnetization as well as coercivity as compare to Cu ion. Hence Co implantation in MgO will be helpful in improving the TMR values for MgO barrier layer based magnetic tunnel junction (MTJ).

Figure 1. XANES and M-H plot of Co and Cu implanted MgO thin films

References [1] J.I. Beltrán, C. Monty, Ll. Balcells, C. Martínez-Boubeta, Solid State Communications, 149, (2009).

[2] Jitendra Pal Singh, Weon Cheol Lim, Jihye Lee, Jonghan Song, Ik-Jae Lee, Keun Hwa Chae; Applied Surface Science 432, 132-139 (2018).

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P40: Study of TiN and ScN thin films

Susmita Chowdhury1, Rachana Gupta1⁕, D. M. Phase2 and Mukul Gupta2 1Institute of Engineering & Technology, DAVV, Khandwa Road, Indore, 452017, India 2UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore, 452001, India Presenting Author’s Email: [email protected] ⁕Corresponding Author’s Email: [email protected] Indus beamline(s) Used: Soft X-Ray Absorption Spectroscopy, INDUS 2, BL- 01

In this work, we present our preliminary results on TiN and ScN thin films deposited using ion beam sputtering (IBS) at room temperature (300 K). TiN thin films, a propitious plasmonic candidate, are prepared with and without titanium (Ti) buffer layer at different beam voltages. Texturing of (111) plane (known to be mechanically harder and more wear resistant) were achieved in the presence of a Ti buffer which could be due to the coherent atomic matching (~98.4%) of the [0002] Ti plane with the (111) plane of TiN leading to minimization of the interfacial strain [1]. Moreover, Ti buffer provides better adhesion between film and the substrate by reducing the residual stress [2]. Golden color of the films further confirms the formation of stoichiometric phase in the samples. ScN is the only stable semiconducting group III-B compound with an indirect band gap of 0.9-1.6 eV [3,4] which led us to deposit ScNx thin films at different N2 pressures. In addition, the (111) plane of ScN provides a lattice matching to the [0001] plane of the most popular GaN and hence they can be used as substrates for the epitaxial growth of GaN [5]. Soft x-ray Absorption Spectroscopy (SXAS) at N K-edge and Ti L-edges in TiN (fig. 1a and 1b); and N K-edge and Sc L-edges in ScN (fig. 1c) provided valuable information about the fundamental electronic and structural properties. Details of these studies will be presented in our presentation. SC and RG are grateful to UGC-DAE CSR, Indore for providing financial support through CSR-IC-BL-62/CSR-179-2016-17/843 project. Thanks are due to L. Behera, A. Gome and R. Sah for the help provided in experiments. SC and RG are grateful to A. K. Sinha, V. Ganesan and

S. Tokekar for suppor t and encouragements. c f (a) (b) TiN_Ti_25nm_1000V (c) e d

a b

TiN_Ti(25nm)_1000V Sc

)

TiN_Ti_10nm_1000V ScN_5E-6 Torr

TiN_Ti(10nm)_1000V

ScN_1E-5 Torr

arb. units

(

 TiN_Ti_10nm_500V

 ScN_2.5E-5 torr

TiN_Ti(10nm)_500V

ScN_5E-5 Torr

ScN_1E-4 Torr

395 400 405 410 415 420 425 430 435 440 450 455 460 465 470 475 480 396 402 408 414 420 426

Energy (eV) Energy (eV) Energy (eV) Fig 1. XAS spectra of N K-edge (a), Ti L-edge (b) of TiN and merged N K-edge, Sc L-edge (c) of ScN thin films. References [1] M. I. Jones, I. R. McColl, D. M. Grant, Surf. Coat. Tech., 132 (2000) 143-151 [2] M. Larsson, M. Bromark, P. Hedenqvist, S. Hogmark, Surf. Coat. Tech., 76 (1995) 202-205 [3] B. Saha, A. Shakouri and T. D. Sands, Appl. Phys. Rev, 5 (2018) 021101-28 [4] S. Kerdsongpanya, N. V. Nong et al, Appl. Phys. Lett, 99 (2011) 232113-3 [5] P. V. Burmistrova, J. Maassen et al, J. Appl. Phys, 113 (2013) 153704. 81

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P41: Study of CrN thin films prepared using Oxygen as surfactant

Rachana Gupta1,Y. Tripathi1, Seema2, D. M. Phase2, P. Rajput2 and Mukul Gupta3 1Institute of Engineering and Technology, DAVV, Indore 2Atomic & Molecular Division, Bhabha Atomic Research Centre, Mumbai 400085 3UGC-DAE Consortium for Scientific Research, Khandwa Road, Indore-452001 Presenting and Corresponding Author’s Email:[email protected] Indus beamline(s) Used: BL 01 and BL 09 Indus 2

Early transition metal nitrides (TMNs) for e.g. TiN, CrN, etc. coatings have become increasingly important in applications where friction reduction, wear resistance and corrosion resistance is required [1-5]. Thin films of CrN have aroused technical interest recently because values of micro hardness are comparable to those of TiN and are easier to deposit by reactive magnetron sputtering. In this work, we deposited a series of Cr-N by systematically varying the deposition parameters like reactive nitrogen gas flow, substrate temperature etc., we find the optimum conditions for preparation of mononitride thin films of Cr.

RN CrN (111) 2

34% (a) CrN (b) 4.6

25% )

-2

Å

( (111)

4.4



RO

2

20%

Cr O units) (arb. Intensity 4.2 2 3 0.5% 16 %

10 % 0.00 0.25 0.50 RO (%)

7% 5 % 2 3.5%

Cr (110) 0.5%

Intensity (arb. uints)(arb. Intensity

2 % 0.25% Reflectivity (arb. units)

1.4%

0.25%

0% exp. 0% 0% fit 30 40 50 60 70 80 0.04 0.06 0.08 0.10 30 40 50 60 70 80 2(degree) -1 q (Å ) 2 (degree) z

Fig. 1: XRD pattern of Cr-N thin films deposited for Fig. 2: XRR (a) and XRD pattern of CrN films different R . N2 prepared with different RO2.

Fig. 3: N K-edge (a) and O K-edge (b) XANES measurements on CrN films with different RO2.

A series of Cr-N thin films were deposited and their XRD pattern for different partial nitrogen gas flow (RN2) are shown in fig. 1. When RN2<2-3%, nanocrystalline Cr(N) phase is formed in which N atoms occupy interstitial position within bcc Cr. For RN2 between 3 to 16%, an amorphous Cr-N phase is 82

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019 formed. When RN2 is increased to 20%, fcc CrN phase start to appear but it is still an N deficient phase and stoichiometric CrN phase appears for RN2=34%. Thermal stability of CrN films was tested by vacuum annealing and by doing XRD and N K-edge XANES measurements after each annealing. While XRD patterns of films annealed up to 873 K (in steps of 200 K) appear similar, we find that significant local deformations taking place above 473 K. By using O as a surfactant, we could find improvement in thermal stability. Signature of O working as a surfactant is visible in the O K-edge XANES spectra (fig. 3b). We find when oxygen gas flow is used at 0.25% of total gas flow, it does not affect long range ordering as shown in fig. 2 but when the amount is increased to 0.5%, the structure becomes amorphous. And in O surfactant mediated film, we find that CrN film possess lower roughness, higher density, close to theoretical Cr-N bond distances and most importantly an improvement in the thermal stability of the CrN films. It can be anticipated that by further fine tuning the surfactant mediated growth of CrN thin films, perfect CrN films having properties matching to their theoretical expected values can be achieved. More details about this work can be found in ref. [6]. This work is performed under CRS of UGC-DAE CSR, Indore with gran no. CSR-IC-BL-62/CRS- 179/2016-17/843. We would like to thank L. Behera, R. Sah, A. Gome and Dr. V. R. Reddy for measurements. RG is grateful to A. K. Sinha, V. Ganesan and S. Tokekar for support and encouragements.

References [1]M. Khadem et al, Friction 5(3),248-262, (2017) [2] D. Wang et al, Vacuum, 143,329-335(2017) [3]F. Ferrelra et al, Surf. Coat. Technol. 291, 365-375 (2016) [4 ]A.S. Botana, et al Phys. Rev Applied 7,024002, (2017) [5] A. Garzon-Fontecha, ey al, Surf. Coat. Tech., 334, 98-104 (2018). [6] Y. Tripathi, R. Gupta, Seema, M. Gupta, D.M. Phase, P. Rajput, Thin Solid Films 670, 113–121 (2019)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P42: Structural, Electronic and Transport Properties of NbNx thin films Shailesh Kalal, Rajeev Rawat and Mukul Gupta* UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India Author’s Email:[email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: Soft X-ray absorption spectroscopy (SXAS) beamline (BL-1) Transition metal nitride (TMN, TM = Ti, Cr, Nb, etc.) thin films attract a great interest for various applications because of their excellent properties such as high hardness, low friction coefficient, high wear and oxidation resistance, thermal and chemical stability. Among them, Niobium nitride (NbN) is a well-known superconductor. In recent years, scientific attention has been focused on the understanding of corrosion behavior as well as the superconducting, mechanical and tribological properties of NbN thin films [1]. In present work, we deposit a series of NbNx thin films at ambient temperature (300 K) by closely varying the amount of reactive nitrogen gas flows (RN2). The XRD pattern shown in fig. a) reveals the formation of textured NbNx films along (111) direction. Fig. b) show superconducting transition temperature for the films as a function of RN2. Highest Tc is obtained for 16% RN2 after which it is continuously decreased and beyond 30% RN2 we did not get transition down to 2 K. In order to investigate electronic properties N K-edge x-ray absorption near edge spectroscopy (XANES) measurement at N- K edge were carried out. In Fig. c) XANES feature a (t2g) and c (eg) arises due to hybridized N (2p) and Nb (4d) orbitals in octahedral NbN6 environment. The crystal field (10Dq) is comes out 3.9 eV, matching well matched others [2]. Feature d arise due higher order transition from N 1s to hybridized 5s-2p orbitals. At higher Nitrogen partial pressure (More than 25%) feature b may arise due to polymeric Nitrogen chains or disorder NbN phase which is one possible reason of suppression of superconductivity [3]. a) b) C)

()

() 100% 13 b a N-K edge

c

80% d

100% 65% Tc 80% 50% 12 65% 40%

50%

30% 11 40%

25% 30% 22.5% 10 25%

20% (K)

c 22.5%

T (arb. unit) (arb. 16%  16% 9

8% 8%

Intensity(arb. unit)

4% 4% 2% 8 2% 1%

0% 1% 7 (100) 0.5%

0%

30 35 40 45 50 55 60 65 70 75 80 6 2(Degree) 0 4 8 12 16 20 24 399 406 413 420 427 434 441 448 RN (%) Energy(eV) 2

Figure (a) XRD patterns (b) N-K edge spectra (c) Variation of critical field with temperature of NbNx thin films deposited at different nitrogen gas flows (RN2). References:

[1] S. P. Chockalingam, M. Chand, J. Jesudasan, V. Tripathi, and P. Raychaudhuri, Phys. Rev. B 77, 214503 (2008). [2] [1] J.G. Chen, Surface Science Reports 30, 1, 152 (1997). [3] M. Chand, A. Mishra, Y. M. Xiong, A. Kamlapure, S. P. Chockalingam, J. Jesudasan, V. Bagwe, M. Mondal, P. W. Adams, V. Tripathi, and P. Raychaudhuri, Phys. Rev. B 80, 134514 (2009)

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P43: Effect of Carbon Doping on Thermal Stability of CoN Thin Films

Yogesh Kumar and Mukul Gupta* UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India Presenting Author’s Email: [email protected]; *Corresponding Author’s Email: [email protected] Indus beamline Used: Soft X-ray absorption spectroscopy (SXAS) beamline (BL-1), Indus-2 In the present work, we investigated the effect of carbon (C) doping on the thermal stability of cobalt mononitride (CoN) thin films. Thermal stability of CoN was found to be poor [1,2] and N tends to diffuse out even at 500 K, making it unsuitable for application point of view. So, there is need to improves its thermal stability. For this, we have used different amounts of C dopings and investigated its effect on the thermal stability of CoN thin films. Polycrystalline films of CoN were deposited by reactive sputtering, using nitrogen alone in a home-made direct current magnetron sputtering (dcMs) sytsem. C doping was achieved by co-sputtering of a C target and its amount was varied by varying the sputtering power (i.e. deposition rates). Thermal stabilty was studied by doing vacuum annealing of films at different temperatures and then by doing XRD and x-ray absorption near edge spectroscopy (XANES) measurements after each annealing. From XRD and N-K edge XANES, we observed that thermal stability of CoN got improved when C doping was about 15% C, and both lower and higher doping was found to be not suitable. Figure 1 shows N K-edge XANES of as-depoited and 523 K annealed samples. As can be seen here N K-edge features disappears when C doping was 0, 5 and 20%. However, with 10% C doping it improves marginally but with 15% C doping it improves significantly. An insight leading to such improved thermal stability will be presented in the presentation.

(a) (b)

20%C

20%C

15%C

15%C

10%C 10%C

(arb. units)

(arb. units)





5%C 5%C

0%C 0%C

390 400 410 420 430 440 390 400 410 420 430 440 Energy (eV) Energy (eV) Fig 1: N K-edge XANES of Co-C-N thin films prepared using in different amount of C in the as- deposited state (a) and after annealing at 523 K (b).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

We are thankful to L. Behera, Nidhi, Prabhat, Seema, Niti and Shailesh for help provided in sample preparation and various measurements. We are also thankful to R. Sah and A. Wadikar for help in XAS measurements. References

[1] K. Suzuki, T. Kaneko, H. Yoshida, H. Morita, and H. J. Fujimori, J. Alloys Compds. 224, 232-236 (1995).

[2] R. Gupta, N. Pandey, A. Tayal, and M. Gupta, AIP Advances 5, 097131 (2015).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P44: Study of Co4N films deposited using dcMS and HiPIMS Seema, Mukul Gupta UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India Presenting Author’s Email: [email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: Soft X-ray absorption spectroscopy (SXAS) beamline (BL-1).[1]

Co4N has simple cubic (anti)perovskite lattice structure where a N atom is located at the body center of a fcc-Co unit cell. The spin polarization of density of states at the Fermi level in Co4N was theoretically predicted to be very high (0.88) which makes it a potential candidate for spintronic materials. However, there have been only a few reports on the growth of single phase epitaxial Co4N thin films deposited at 673 K where magnetic properties of compound have been studied using x-ray circular dichroism (XMCD) [2]. For Co-N system the phase diagram has not been established yet. The theoretical calculated lattice parameter (LP) of Co4N and cubic (fcc) Co are 3.73 and 3.52 Å, respectively. Various reports for film and powder Co4N, the reported values of LP are about 3.58 Å, indicating N- deficiency. Self-diffusion studies in Co-N system revealed that N diffusion is significantly faster in Co-N. Even at substrate temperature of 523 K, N out-diffusion takes place which have been studied by depositing the polycrystalline Co-N films by dc magnetron sputtering (dcMS), the phase formed was fcc Co indicating profound N diffusion at the time of deposition [3]. In the view of this we have made attempts to deposit Co-N films at 300 K by two methods (i) changing the orientation of films: utilizing (111) oriented TiN buffer layer (ii) by controlling growth kinetics using variation in ad-atom mobility: by using High Power Impulse Magnetron Sputtering (HiPIMS). Structural and magnetic properties of polycrystalline Co-N deposited films were studies using XRD, XMCD, S-VSM and PNR. XRD data reveal Co4N phase formation and oriented films. X-ray absorption spectra for L-edge of Co and K-edge of N were taken in with magnetic field at BL-1, RRCAT to calculate spin magnetic moment. S-VSM and PNR data, shows that the presence of TiN buffer layer does not affect the magnetic properties significantly. However, the value of saturation magnetization matches previously reported values ~ 1.6B/Co atom [4].

References:

[1] D. M. Phase, M. Gupta, et. al., AIP Confer. Proceed. 1591, 685 (2014).

[2] K. Ito, et. al., Applied Physics Letters 99, 252501 (2011).

[3] N. Pandey et. al. Journal of Magnetism and Magnetic Materials 448 (2018) 274-277.

[4] S. F. Matar et. al. Phys. Rev. B 75, 245109 (2007).

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

P45: XAS study of growth parameters for formation of FeN thin films Niti1, Mukul Gupta1* and Parasmani Rajput2 1UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452001, India 2 Atomic & Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085, India Presenting Author’s Email:[email protected]; Corresponding Author’s Email: [email protected] Indus beamline(s) Used: Soft X-ray absorption spectroscopy (SXAS) beamline (BL-1) and Scanning EXAFS beamline (BL-9). Abstract: Various compositions exist in iron nitride (Fe-N) system. Among them, Fe-rich phases have been explored very well owing to their various magnetic applications while only few reports have dealt with N-rich phase such as iron mononitride (FeN) formed for equiatomic composition of Fe and N. Theoretically, it was reported that this compound might have two crystal structures, one is rock salt-type (RS) and other is zinc blend-type (ZB) [1,2]. However, experimentally only ZB-type has been reported unlike other transition metal mononitrides (TMMN) which are stable in RS-type structure as enthalpy of formation of FeN is higher than early TMMN which leads to thermal instability of this compound. Apart from fundamental interest, FeN is also used as a promising precursor material to prepare magnetic FeN compounds which are viable for application in spintronics. Earlier we have deposited FeN films at room temperature in which an anomaly was found in diffusion behaviour of Fe and N atoms, Fe being larger atom diffuses faster than N due to dominant grain boundary diffusion [3]. So in order to minimize the grain boundaries, in this work, we have studied the phase formation of FeN thin films at various substrate temperatures (Ts). FeN films are characterized for their long range ordering using x-ray diffraction (XRD) and local structure has been studied using x-ray absorption spectroscopy (XAS) obtained at Fe and N-K edges. From XRD pattern, it was found that FeN films with lattice parameter (LP) close to its theoretical value (4.2 Å) can be formed at Ts = 423 K. XAS measurements at N and Fe-k edge also reveal that FeN films deposited at 423 K shows lowest value of b/a ratio and highest intensity of pre-edge corresponding to maximum tetrahedral coordination between Fe and N atoms (ZB-type structure).

(a) 4.312 (b) ) 0.36

a (c)

/ 398 K

4.305 b (

0.32 0.9 423 K

(111) 4.298 448 K

LP (Å) LP a 0.28

4.291 Ratio 4.284 400 420 440

400 420 440 Ts (K) 0.6

Ts (K) b 448 K 448 K (222)

(arb. units) Pre-edge



(arb. units) (arb.

423 K  (220) (arb.units) 0.3

423 K 

7112 7114 7116

398 K Intensity (arb. units) Intensity Energy (eV) 398 K 0.0 7100 7120 7140 7160 7180 30 40 50 60 70 80 400 410 420 430 440 2(degrees) Energy (eV) Energy (eV) Fig 1: (a) XRD and XAS spectra taken at (b) N-k edge and (c) Fe-k edge of FeN thin films deposited at different Ts.

References: [1] A. Filippetti et al, Phys. Rev. B 59, 8397 (1998).

[2] P. Lukashev et al, Phys. Rev. B 70, 245205 (2004).

[3] A. Tayal et al, Phys. Rev. B 92, 054109 (2015). 88

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

List of Principal Collaborators for ISUM 2019 Indus 2 BEAM LINE Principal Collaborators Soft X-ray BL-1 Dr.D.M.Phase [email protected] 0731-246 1. Absorption Dr. Mukul Gupta [email protected] 3913 0731-244 2501 Soft X-ray BL-3 Dr. M.H. Modi [email protected] 731 244 2121 2. Reflectivity (100-1500 eV) Imaging BL-4 Dr. Ashish Agarwal [email protected] 731 244 3. beamline 2599/ 2504

4. X-Ray BL-7 Dr. A.K. Shrivastava [email protected] 0731-244 Lithography 2174/ 2507 EXAFS BL-8 Dr. S.N. Jha [email protected] 0731-244 5. Dr. D. Bhattacharyya [email protected] 2104/ 2508 Scanning BL-9 Dr. S.N. Jha [email protected] 0731-244 6. EXAFS Dr. D. Bhattacharyya [email protected] 2104/ 2509

Extreme BL-11 Dr. H.K. Poswal [email protected] 022- 7. conditions Dr. Velaga Srihari 25592753/ AD/ED-XRD 0731 244 [email protected] 2511

8. Angle BL-12 Dr. A.K. Sinha [email protected] 0731-244 Dispersive XRD 2103/ 2512

9. GIXS BL-13 Dr. Satyaban Bhunia [email protected]

XPES BL-14 Dr. Uttam K Gautam [email protected] 0731-244 10. 2118/ 2514 Dr. Jagannath [email protected]

11. X-ray BL-16 Dr. M.K. Tiwari [email protected] 0731-244 Fluorescence 2103/ 2516 Protein BL-21 Dr. R.D. Makde [email protected] 0731-244 12. Crystallography Dr. Biplab Ghosh [email protected] 2175/ 2521

Indus-1 1. HRVUV BL-1 Dr. S.N. Jha [email protected] 0731-244 2104/ 2531 Angle BL-2 Dr. D.M.Phase [email protected] 0731- 2463913 2. Integrated PES Dr. Ram Janay [email protected] Choudhary

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

3. Angle Resolved BL-3 Dr. S.N. Jha [email protected] 0731-244 PES 2104/ 2533 Soft X-ray BL-4 Dr. M. H. Modi [email protected] 0731-244 4. Reflectivity 2121/ 2534 (10-300 eV) 5. Photophysics BL-5 Dr. B.N. Rajasekhar [email protected] 0731-248 8141 [email protected] 6. Infrared BL-6 Shri Himal Bhatt

PASS BL-7 Shri R.K. Sharma [email protected] 0731 244 7. 2118/ 2537

Detailed information about beamline can be found at:

INDUS-2: http://www.rrcat.gov.in/technology/accel/srul/beamlines/index.html

INDUS-1 http://www.rrcat.gov.in/technology/accel/srul/indus1beamline/index.html

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

ISUM 2019- List of participants Invited Speakers S. No. Name Affiliation 1. Prof. A. K. Raychaudhuri S.N.Bose National Centre for Basic Sciences, Kolkata 2. Dr. Tapas Ganguli RRCAT, Indore 3. Dr. S. Mukherjee IIT Indore 4. Dr. R. J. Choudhary UGC DAE CSR, Indore 5. Dr. Mukul Gupta UGC DAE CSR, Indore 6. Dr. Smita Acharya RTM Nagpur University, Nagpur 7. Dr. Chandrani BARC, Mumbai 8. Dr. Devaraj Nataraj Bharathiar University, Coimbatore 9. Dr. D. M. Phase UGC-DAE CSR, Indore 10. D. Bhattacharyya BARC, Mumbai 11. Dr. Ashish Agrawal BARC, Mumbai 12. Dr. Pushpen Mondal RRCAT, Indore 13. Dr. U. K. Gautam BARC, Mumbai 14. Dr. Debasis Sen BARC, Mumbai 15. Dr. Sanajay Rai RRCAT, Indore 16. Dr. V. Srihari BARC, Mumbai 17. Prof. Ajay Gupta Amity Univ., Noida 18. Prof. D. G. Kuberkar Saurashtra University, Rajkot 19. Prof. B.D. Shrivastava, Ujjain 20. Prof. MSR Rao IIT Madras, Chennai 21. Dr. A. Dalvi, BIT & Science, Pilani 22. Dr S. Bandyopadhyay University of Calcutta, Kolkata 23. Dr Bivas Saha JNCSR, Bangalore 24. Dr. Bindu Radhamany IIT Mandi 25. Dr. S. K. Shrivastava IIT Kharagpur 26. Dr. Aloke Kanjilal SNU, Gautam Buddha Nagar, UP 27. Dr Ashok Kumar Yadav BARC, Mumbai 28. Dr. Param Jeet Singh BARC, Mumbai 29. Prof. P. Sen DAVV, Indore 30. Dr. Shailendra Kumar UGC-DAE CSR, Indore 31. Dr. Archana Sagdeo RRCAT, Indore 32. Dr. Soma Banik RRCAT, Indore 33. Prof. S. N. Kane DAVV, Indore 34. Prof. Ratnesh Gupta DAVV, Indore 35. Dr. R. N. Bhowmik Pondicherry University 36. Dr. Vivek Malik IIT Roorkee 37. Dr. Sanjay Nayak IKST, Bangalore 38. Dr. Kiran Singh Dr. B.R. Ambedkar NIT, Jalandhar 39. Dr. Pankaj Sagdeo IIT Indore 40. Dr. Fouran Singh IUAC, New Delhi 41. Prof. S. Chaterjee IIT BHU, Varanasi 42. Dr. R. K. Gupta, RRCAT, Indore 43. Prof. K.N. Uttam University of Allahabad, Allahabad 92

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

Registered Participants (Faulty) 44. Dr. S. Srinivasan Presidency College (Autonomous), Chennai 45. Dr. Mahesh Kumar Indian Institute of Technology Jodhpur 46. Veera Bhadraiah Sadhu School of Physical Sciences Banasthali Vidyapith – 304022, Rajasthan 47. G. MANJULA KAKATIYA UNIVERSITY, WARANGAL, TELANGANA STATE, INDIA. 48. Dr. N. Ayyadurai CSIR-Central Leather Research Institute 49. TAHIR MURTAZA GOVT. DEGREE COLLEGE GANDERBAL KASHMIR 50. Dr. Sanjiv Puri Department of Basic and Applied Sciences, Punjabi University, Patiala, Punjab 147002 51. Dr Poornesh Kumar NITK Surathkal Koorata 52. PARNIKA DAS Variable Energy Cyclotron Centre 53. Dr. Ashwin Mohan Institute of Chemical Technology, Mumbai 54. Dr. Vanarajsinh Solanki Dr. K. C. Patel R & D Centre, Charusat University, Changa, Gujarat-388421 55. Dr. Hardeep Kumar NIT Uttarakhand, Srinagar (Garhwal) 56. Dr Shikha Wadhwa Amity University Uttar Pradesh 57. Seema Sharma Department of physics, AN College, Patna 58. R.N. Bhowmik Department of Physics, Pondicherry University 59. Pawan Kumar Jha Centre of Envirment Studies, University of Allahabad 60. Sadaf Jethva Department of Nanoscience, Saurashtra University, Rajkot 61. Mandar M. Shirolkar Symbiosis Center for Nanoscience and Nanotechnology, Symbiosis International (Deemed University) 62. Dr P S Goyal Pillai College of Engineering, New Panvel 63. Monika Joshi Amity Institute of Nanotechnology, Amity University, Uttar Pradesh , Noida 64. Dr. Preeti Jain Medi-Caps Uni. Indore 65. Dr. Kamkhya Prakash Manipal University Jaipur Misra 66. Sivarama Krishnan Indian Institute of Technology Madras 67. A. Murugadoss University of Madras, Guindy Campus, Chennai 68. Ashish Prabhakar Fergusson college, Pune Yengantiwar 69. Chetan K. Modi The Maharaja Sayajirao University of Baroda, Vadodara 70. Om Prakash Sinha Amity University, Noida 71. M.K.Dwivedi Govt. Holkar Science College Indore 72. M.A. SHaz Banaras Hindu University, Varanasi 73. Anurag Trivedi Lupin Research Park, Pune 74. P. Padmaja Sudhakar The Maharaja Sayajirao University of Baroda 75. Yogesh Satpute Lupin Research Park, Pune

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76. Nidhi Tiwari Lupin Research Park, Pune 77. Sajal Kumar Ghosh Shiv Nadar University 78. Neelu Chouhan University of Kota, Kota 79. Jitendra Solanki Shri Vaishnav Vidyapeeth Vishwavidyalaya, Indore 80. Sumalay Roy University of Delhi, Delhi 81. Sudipta Bandyopadhyay University of Calcutta, Kolkata 82. Vandana Rathore Jagran Lakecity University, Bhopal 83. Jeetendra Bhawsar Medi-Caps University Indore 84. Arun Lal Srivastav Chitkara University, Himachal Pradesh 85. Varinder Singh Kanwar Chitkara University, Himachal Pradesh 86. M. Junaid Bushiri University of Science and Technology Kochi 87. B.K. Mehta Vikram University Ujjain(M.P.) 88. Rahul Singal Malaviya National Institute of Technology Jaipur 89. Nilanjan Halder Manipal University Jaipur 90. Rahul Shrivastava Maulana Azad National Institute of Technology, Bhopal 91. Kavita Sharma Amity University UP 92. Ashis Biswas Indian Institute of Science Education and Research Bhopal 93. Balaji P Mandal Bhabha Atomic Research Centre, Mumbai 94. Sunil D. Kulkarni Sir Parashurambhau College, Pune 95. P. Padmaja Sudhkar The Maharaja Sayajirao University of Baroda 96. Aman Mahajan Guru Nanak Dev University, Amritsar, Punjab 97. Dr. Ambesh Dixit IIT Jodhpur 98. Dr. S.Arumugam CHPR Bharathidasan University Tiruchirapalli 99. Parnika Das Nuclear Physics and Solid State Physics, VECC Kolkata 100. Dr. Guruprasad Mandal Jadavpur university, Kolkata 101. Dr. Chandana Rath School of Materials Science and Technology IIT(Banras Hindu University), Varanasi, India 102. Dr. Manish Kumar Banasthali Vidyapith, Rajasthan-304022 Srivastava 103. Dr. Sandeep Kumar Manipal University Jaipur Srivastava 104. Aiswarya Bhaskar CSIR-CECRI 105. Dr. P. Predeep NIT Calicut Kerela 106. Lt. Dr. Prashant W. Dharampeth M. P. Deo Memorial Science College, Ambekar Nagpur 107. Dr. Srinivasa Rao Malaviya National Institute of Technology Jaipur Nelamarri 108. Dr. Ashima Bagaria Manipal University Jaipur 109. Noor Aman Ahrar B.S. Abdur Rahman Crescent Institute of Science Mundari and Technology 110. Dr. Ajit K Patra Central University of Rajasthan 111. Dr. Arpita Bhattacharya Amity Institute of Nanotechnology, Amity University, Uttar Pradesh

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112. Dr. Sanchita Department of Mechanical Engineering, Manipal Bandyopadhyay-Ghosh University, Jaipur 113. Prof. Jaya Dwivedi School of Life Sciences Natural Product Chemistry Environmental Science 114. Prof. Kailash Narayan University of Allahabad, Uttam Allahabad 115. Dr. Md. Harunar Rashid Physical and Materials Chemistry 116. Dr. Aravind S. Bennal Karnataka University 117. Dr. Supratim Mitra Department of Physics, Banasthali Vidyapith 118. Anthony Amrulraj Sastra Deemed University, Tirumalaisamudram, Thanjavur 119. Dr. Rajendra S. Dhaka Indian Institute of Technology Delhi, Hauz Khas, New Delhi 120. Dr. Sancharini Das Amity University Uttar Pradesh, Noida campus 121. Dr. Supratim Mitra Department of Physics, Banasthali Vidyapith

122. Dr. R.N. Bhowmik Pondicherry University, R. Venkataraman Nagar, Kalapet, Pondicherry 123. Dr. Sunil Kumar Arora Centre for Nanoscience and Nanotechnology, Block- II, South Campus, Panjab University, Sector-25, Chandigarh-160014, India. 124. Dr. Mamatha D Daivajna MIT, MAHE Manipal Karnataka 125. Prof. Prafulla K. Jha The Maharaja Sayajirao University of Baroda, Vadodara 126. Fozia Aziz Shri G. S. Institute of Technology and Science, Indore 127. Veera Bhadraiah Sadhu School of Physical Sciences Banasthali Vidyapith – 304022, Rajasthan 128. Rahul Singal Department of Physics, Malaviya National Institute of Technology Jaipur 129. Dr. Rachana Gupta IET, DAVV, Indore 130. A. P. Deshpande Matoshri Nanibai Gharphalkar Science College,Babhulgaon-445101 (Maharashtra) 131. Savan Katba RK University, Rajkot 132. Amit Sharma Jamia Millia Islamia, New Delhi Registered Participants (Students) 133. Disha Harinkhere GOVT. HOLKAR SCIENCE COLLEGE, INDORE 134. POORNIMA KARIL GOVT. HOLKAR SCIENCE COLLEGE, INDORE 135. NIKITA KARMA GOVT. HOLKAR SCIENCE COLLEGE, INDORE 136. PUNEET KAUR DEPARTMENT OF PHYSICS, GURU NANAK DEV UNIVERSITY, AMRITSAR, PUNJAB 137. P NANDHAKUMAR Pondicherry University R.V.Nagar Kalapet, Puducherry- 138. Rahul Centre for Nanoscience and Nanotechnology, Panjab uni, Chandigarh 139. Omvir singh CSIR-IIP Dehradun 140. Harikrishnan R Dep. of Physics, IIT, Madras 95

Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

141. Deependra Parajuli Department of Physics, College of Science and Technology, Andhra University 142. Satya Prakash Tiwari Guru Jambheshwar University of Science and Technology 143. JYOTI MONDAL IISER BHOPAL, INDIA 144. Srikanth Pedireddy King Abdullah University of Science and Technology, Water Desalination and Reuse Center 145. Raja Preethi.V Crystal growth Centre, Anna University. Chennai. 146. K. PAUL REDDY DEPARTMENT OF INORGANIC CHEMISTRY, UNIVERSITY OF MADRAS, CHENNAI-600 025 147. A.CATHERINE DEPARTMENT OF INORGANIC CHEMISTRY, SWETHA UNIVERSITY OF MADRAS, CHENNAI-600 025 148. Vasu. S Metallurgical and Materials Engineering, IIT Madras 149. Swati Nagar SOP, DAVV 150. PRIYANKA SINGH Centre of Material Sciences, University of Allahabad 151. Swati Pandey UGC DAE Consortium for Scientific Research Mumbai Centre 152. Pawan Kumar Tiwar Department of Biophysics, AIIMS 153. Nitin Shinde SRM Institute of Science and Technology, Chennai 154. Aruna Joshi School Of Physics Devi Ahilya University Indore 155. Krishna Kant Dubey IIT (BHU) Varanasi 156. ANUPAM KUMAR School of Materials Science and Technology SINGH Indian Institute of Technology (BHU), Varanasi-221005, UP, India. 157. SHIPRA GUPTA School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi-221005, U. 158. SANDEEP KUMAR IIT (BHU), Varanasi 159. Nisha Shahi School of Material Science and Technology IIT-BHU, Varansi 160. M. Kannn Centre for High Pressure Research Department of Physics, Bharathidasan University Tiruchirappalli- 620024-Tamil Nadu 161. Amit Kumar School of Materials Science and Technology Indian Institute of Technology (BHU), Varanasi-221005, UP, India. 162. Yashpal Yadav Biochemical Sciences Divison, CSIR-National Chemical Laboratory, Pune-08 163. Sanchita Ajay Borkar Savitribai Phule pune University,Pune 164. Balram Patidar Medi-Caps Uni. Indore 165. ANANDHAN. J Tamil Nadu Agricultural University 166. Manisha INST, Mohali 167. Tahir Yaqoob SOP, DAVV 168. Harshil Agarwal Department of Physics, Banaras Hindu University, Varanasi-221005 169. Atul Tiwari Amity Centre for Spintronic Materials 170. Neeta Gurbani Department of Pure and Applied Chemistry

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University of Kota, Kota 171. Rajashri Ramchandra Department of Physics, Rashtrasant Tukadoji Urkude Maharaj Nagpur University, Nagpu 172. Yashmeen Jafri Amity University, Noida, Uttar Pradesh-201313 173. Deependra Parajuli Department of Physics, Andhra University 174. NANDHINI T Arignar Anna Government Arts College, Namakkal - 637 002 175. Mayanglambam Dept. of Physics, BITS Pilani-Pilani Campus Dinachandra Singh 176. Priyanka Gupta Jagran Lakecity University, Bhopal 177. Priya Singh Department of ceramic Engineering IIT-BHU, Varanasi 178. Satyajeet Das Amity institute of biotechonolgy, Jaipur 179. Gopal Avashthi School of Chemical Sciences, Central University of Gujarat, Gnadhinagar-382030 180. Sharma School of studies in chemistry & Biochemistry, Vikram university Ujjain, M.P. 181. Namrata Khanna Amity Institute of Nanotechnology, Amity University, Noida, U.P. 182. Payal Manzi AMITY INSTITUTE OF NANOTECHNOLOGY, AMITY UNIVERSITY, UP, SECTOR-125, EXPRESS HIGHWAY, NOIDA- 201303 (INDIA) 183. Divya Patel Chemistry Department, Faculty of science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 184. Renuka Kendurkar School of Studies in Physics, Vikram University, Ujjain. (M.P.) 185. Naznin A. Shaikh Department of Chemistry, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat 186. Nancy Central University of Rajasthan, Ajmer 187. Kiranjot HBNI, RRCAT 188. Niti UGC DAE CSR, Indore 189. Seema UGC DAE CSR, Indore 190. Shailesh Kalal UGC DAE CSR, Indore 191. Romita Chouan SOP, DAVV Indore 192. Shuja la Praveen Sheikh SOP, DAVV Indore 193. Preeti Pokhriyal HBNI RRCAT 194. Vishnukant Swami Vivekananda Global University, Jaipur 195. Shubham Jain Vivekananda Global University, Jaipur 196. Devendra Pal Lata Vivekananda Global University, Jaipur 197. Dayaram Sharma Vivekananda Global University, Jaipur 198. Kapil Soni Vivekananda Global University, Jaipur 199. Hardepinder Singh Department of Sciences and Humanities NIT Uttarakhand, Srinagar, Garhwal 200. KHUSHBOO AMITY UNIVERSITY, NOIDA BUKHARIA

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

201. Amol Shankar Lihitkar Dept. of Physics, RTM Nagpur University, Nagpur 202. Aakash Bhadreshkumar Dept. of Mechanical Engg., IIT Bombay, Mumbai Patel 203. Priyanka Baraskar School of Physics, Devi Ahilya University, Indore 204. Abhi Sarika Bharti Centre for Environmental Science University of Allahabad, Allahabad 205. Navpreet INST, Mohali 206. Sweta Sharma University of Allahabad, Allahabad 207. Pramod Vishwakarma ACSM, Amity University, Noida 208. Anupam Jana UGC DAE CSR, Indore 209. Deepak Upadhyay The Maharaja Sayajirao University of Baroda, Vadodara 210. Ms. Divya Arumugam PG and Research Department of Physics NMSSVN College Nagamalai, Madurai 211. ATEEQ AHMED Dept. of Applied Physics, AMU, Aligarh, UP 212. Abhishek G.S. Dept. of Mechanical Engg., IIT – Bombay 213. Aniket Waykos Department of Physics. SPPU 214. Dr. Madhushree Bute Department of Technology, SPPU 215. Ritu Rawat UGC DAE CSR, Indore 216. MONA GUPTA GOVT. PG COLLEGE KOTDWAR UTTARAKHAND 217. Gyanendra Panchal UGC DAE CSR, Indore 218. Yogesh Kumar UGC DAE CSR, Indore 219. Gangadharayya B Department of Physics, Hiremath Karnatak University, Dharwad-580003 220. JAGRATI DWIVEDI School of Physics, Devi Ahilya University, Indore (MP) 221. Shmrad Babu Pillai The Maharaja Sayajirao University of Baroda, Vadodara 222. Nidhi Pandey UGC-DAE CSR, Indore 223. Gaurav Sharma UGC-DAE CSR, Indore 224. Shekhar Tyagi UGC-DAE CSR, Indore 225. Payal Manzhi AMITY INSTITUTE OF NANOTECHNOLOGY, AMITY UNIVERSITY, UP, NOIDA 226. Vibha Malviya -- 227. Patel Arif Mohiuddin School Of Physical Sciences KBCNMU Jalgaon 228. Manoj Kumar Himachal Pradesh University Shimla 05 229. Susmita Chowdhury IET, DAVV, Indore 230. Aakanksha Choudhary SOP, DAVV

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

ISUM 2019- PARTONS

S. No. Name Affiliation

231. Prof. N. K. Dhakad Vice-Chancellor, DAVV, Indore

232. Prof. P. A. Naik, Director, RRCAT, Indore

233. Dr. A. K. Sinha Director, UGC-DAE CSR

ISUM 2019- ORGANIZING COMMITTEE

Dr. V. Ganesan, Chairman Centre-Director, UGC-DAE CSR, Indore 234.

235. Prof. A. Mishra HOD, SOP, DAVV, Indore

236. Dr. Tapas Ganguli Head, SUS, RRCAT, Indore

Dr. D. M. Phase UGC-DAE CSR, Indore 237. (Convenor ISUM 2019)

238. Prof. P. Sen SOP, DAVV, Indore

239. Prof. S. N. Kane SOP, DAVV, Indore

, HOD, SOI, DAVV Indore 240. Prof. Ratnesh Gupta

241. Dr.S.N.Jha BBS, RRCAT/BARC, Indore

242. Dr.A.K.Sinha SUS, RRCAT, Indore

243. Dr.M.H.Modi SUS, RRCAT, Indore

Dr. R. J. Choudhary 244. UGC-DAE CSR, Indore (Co-Convenor ISUM 2019)

Dr. Mukul Gupta 245. (Co-Convenor ISUM 2019), UGC-DAE CSR, Indore

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Indus Synchrotrons Users’ Meeting (ISUM) March 27-29, 2019

ISUM 2019- Local Organizing Committee (UGC-DAE CSR, Indore) S. No. Name 1. Dr. D. M. Phase 2. Dr. Mukul Gupta 3. Dr. R. J. Choudhary 4. Dr. V. R. Reddy 5. Dr. Rajeev Rawat 6. Er. P. Saravanan 7. Er. S. S. Thakur 8. Er. Bhushan Jain 9. Dr. Archna Lakhani 10. Dr. Venkatesh 11. Dr. Rajamani 12. Sh. Devendra Singh 13. Sh. Rajeev Bhagwat 14. Sh. Ashish Upadhyaya 15. Dr. S. Potdar 16. Sh. J. V. Sharma 17. Sh. A. Wadikar 18. Sh. A. Gome 19. Sh. Manoj Kumar 20. Mr. Layanta Behera 21. Mr. Rakesh Sah 22. Sh. Sharad Karwal 23. Sh. C. L. Dwivedi 24. Sh. Rakesh Kumar 25. Sh. Vishnu Kaushal 26. Sh. R. Bhimgade

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