CV Vassilia Zorba 01-2020
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
FY20 National Laser Users' Facility Program
FY20 NATIONAL LASER USERS’ FACILITY PROGRAM FY20 National Laser Users’ Facility Program M. S. Wei Laboratory for Laser Energetics, University of Rochester During FY19, the National Nuclear Security Administration (NNSA) and Office of Science jointly completed a funding opportu- nity announcement (FOA), review, and selection process for National Laser Users’ Facility (NLUF) experiments to be conducted at the Omega Facility during FY20 and FY21. After peer review by an independent proposal review committee for scientific and technical merit and the feasibility review by the Omega Facility team, NNSA selected 11 proposals for funding and Omega shot allocation with a total of 22.5 and 23.5 shot days for experiments in FY20 and FY21, respectively. During the first half of the FY20, LLE completed a one-time solicitation, review, and selection process for Academic and Industrial Basic Science (AIBS) experiments to utilize the remaining NLUF shot allocation in FY20–FY21. Ten new projects were selected for AIBS shot alloca- tion (a total of 11 and 10 shot days) for experiments staring in Q3FY20 and throughout FY21. FY20 was the first of a two-year period of performance for these 21 NLUF including AIBS projects (Table I). Fifteen NLUF and AIBS projects obtained a total of 232 target shots during FY20, which are summarized in this section. A critical part of the NNSA-supported NLUF program and the DOE Office of Fusion Energy Sciences (FES)-supported Laser- NetUS program is the education and training of graduate students in high-energy-density (HED) physics. In addition, graduate students can also access the Omega Laser Facility to conduct their theses research through collaborations with national labora- tories and LLE. -
A Programmable Mode-Locked Fiber Laser Using Phase-Only Pulse Shaping and the Genetic Algorithm
hv photonics Article A Programmable Mode-Locked Fiber Laser Using Phase-Only Pulse Shaping and the Genetic Algorithm Abdullah S. Karar 1,* , Raymond Ghandour 1 , Ibrahim Mahariq 1 , Shadi A. Alboon 1,2, Issam Maaz 1, Bilel Neji 1 and Julien Moussa H. Barakat 1 1 College of Engineering and Technology, American University of the Middle East, Kuwait; [email protected] (R.G.); [email protected] (I.M.); [email protected] (S.A.A.); [email protected] (I.M.); [email protected] (B.N.); [email protected] (J.M.H.B.) 2 Electronics Engineering Department, Hijjawi Faculty for Engineering Technology, Yarmouk University, Irbid 21163, Jordan * Correspondence: [email protected] Received: 24 July 2020; Accepted: 2 September 2020; Published: 4 September 2020 Abstract: A novel, programmable, mode-locked fiber laser design is presented and numerically demonstrated. The laser programmability is enabled by an intracavity optical phase-only pulse shaper, which utilizes the same linearly chirped fiber Bragg grating (LC-FBG) from its two opposite ends to perform real-time optical Fourier transformation. A binary bit-pattern generator (BPG) operating at 20-Gb/s and producing a periodic sequence of 32 bits every 1.6 ns, is subsequently used to drive an optical phase modulator inside the laser cavity. Simulation results indicate stable programmable intensity profiles for each optimized user defined 32 code words. The laser operated in the self-similar mode-locking regime, enabling wave-breaking free operation. The programmable 32 bit code word targeting a specific intensity profile was determined using 100 generations of the genetic algorithm. -
MRI-Guided Laser Ablation Surgery of Hypothalamic Hamartomas
NEUROSURGERY MRI-Guided Laser Ablation Surgery of Hypothalamic Hamartomas HOW DOES THE TEAM DECIDE IF A PATIENT IS A CANDIDATE FOR MRI-GUIDED LASER ABLATION? A careful review of each patient’s medical records is the first step, including MR imaging of the brain and any applicable neurology or neurosurgery records. Patients with Hypothalamic Hamartomas (HH) typically have gelastic seizures, which are characterized by emotionless laughing, although variations including abnormal movements or staring spells are also common. Every patient’s case is handled individually, and it may be necessary for a patient to come to Texas Children’s Hospital for further testing to determine if they are a candidate for MRI-guided laser ablation surgery. WHAT HAPPENS DURING MRI-GUIDED LASER ABLATION SURGERY? After being placed under general anesthesia, a head frame, or a set of markers, is fitted to the patient’s skull. A CT scan is completed to orient the brain to the frame in 3 dimensions. With the help of computer software, a safe pathway that goes through the brain to the HH is calculated for the laser. The neurosurgeon then makes a small incision and drills a small hole through the skull (3.2 mm wide). The laser applicator, a small tube about the width of a strand of spaghetti, is inserted and guided through the brain into the HH. Once the laser applicator is inserted into the brain, the head frame is removed, and the patient is transported to the MRI scanner. After confirming proper placement of the laser applicator and setting safety markers, the surgeon performs a small test firing using the laser. -
Next Generation High Temperature Superconducting Wires” A
To be published in “Next Generation High Temperature Superconducting Wires” A. Goyal (Ed.), Kluwer Academic/Plenum Publishers PULSED LASER DEPOSITION OF YBa2Cu3O7-δ FOR COATED CONDUCTOR APPLICATIONS: CURRENT STATUS AND COST ISSUES Hans M. Christen Oak Ridge National Laboratory Solid-State Division Oak Ridge, TN 37831-6056 INTRODUCTION Amongst the numerous techniques currently being tested for the fabrication of coated conductors (i.e. high-temperature superconducting oxides deposited onto metallic tapes), pulsed laser deposition (PLD) plays a prominent role. Recent results from groups in the United States (e.g. Los Alamos National Laboratory), Europe (e.g. University of Göttingen), and Japan (e.g. Fujikura Ltd.) are most promising, yielding record numbers for Jc and Ic. As a method for depositing films of complex materials, such as the high-temperature superconductors (HTS) relevant to this chapter, PLD is well established and conceptually simple. Issues that have kept PLD from becoming a successful technique for devices and optical materials, namely particulate formation and thickness non-uniformities, are much less of a concern in the fabrication of HTS tapes. Nevertheless, the approach still presents ongoing challenges in the fundamental understanding of the laser-target interaction and growth from the resulting energetic plasma plume. Numerous issues related to the scale-up, control, reproducibility, and economic feasibility of PLD remain under investigation. It is clearly beyond the scope of this short chapter to give a complete treatise of such a complex subject – fortunately, several excellent reviews have already been published.1-3 It is thus the intent of the author to introduce PLD only briefly and with a strong focus on HTS deposition, summarizing the most important developments and referring the reader to the numerous cited works. -
Femtosecond-Pulsed Laser Deposition of Erbium-Doped Glass Nanoparticles in Polymer Layers for Hybrid Optical Waveguide Amplifiers
Femtosecond-Pulsed Laser Deposition of Erbium-Doped Glass Nanoparticles in Polymer Layers for Hybrid Optical Waveguide Amplifiers. Eric Kumi Barimah*1, Marcin W. Ziarko2, Nikolaos Bamiedakis2, Ian H. White2, Richard V. Penty2, Gin Jose1 School of Chemical and Process Engineering, University of Leeds, Clarendon Road, Leeds LS2 9JT, United Kingdom Centre for Photonic Systems, Department of Engineering, University of Cambridge, 9 JJ Thomson Ave, Cambridge CB3 0FA, United Kingdom *[email protected] Tellurium oxide (TeO2) based glasses are widely used in many applications such as fibre optic, waveguide devices and Raman gain, and are now being considered for use in optical waveguide amplifiers. These materials exhibit excellent transmission in the visible and near IR wavelength range (up to 2.0 µm), low phonon energy, and high rare-earth solubility [1-3]. Siloxane polymer materials on the other hand, have remarkable thermal, mechanical and optical properties and allow the fabrication of low-loss optical waveguides directly on printed circuit boards. In recent years, various low-cost optical backplanes have been demonstrated using this technology [4-7].However, all polymer optical circuits used in such applications are currently passive, requiring therefore amplification of the data signals in the electrical domain to extend the transmission distance beyond their attenuation limit. The combination of the TeO2 and siloxane technologies can enable the formation of low-cost optical waveguide amplifiers that can be deployed in board-level communications. However, there are significant technical challenges associated with the integration of these two dissimilar materials mainly due to the difference in their thermal expansion coefficients. In this paper therefore, we propose a new approach for incorporating erbium (Er3+)-doped tellurium- oxide glass nanoparticles into siloxane polymer thin films using femtosecond pulsed laser deposition (fs-PLD). -
With Short Pulse • About 7% Coupling Significantly Less Than the Osaka Experiment
Electron/proton generation from solid targets and applications Farhat Beg University of California, San Diego This work was performed under the auspices of the U.S. DOE under contracts No.DE-FG02-05ER54834, DE-FC0204ER54789 and DE-AC52-07NA27344. We greatly acknowledge support of Institute for Laser Science Applications, LLNL. Committee on Atomic, Molecular and Optical Sciences Meeting The National Academy of Sciences Washington DC, April 5, 2011 1 Summary ü Short pulse high intensity laser solid interactions create matter under extreme conditions and generate a variety of energetic particles. ü There are a number of applications from fusion to low energy nuclear reactions. 10 ns ü Fast Ignition Inertial Confinement Fusion is one application that promises high gain fusion. ü Experiments have been encouraging but point towards complex issues than previously anticipated. ü Recent, short pulse high intensity laser matter experiments show that low coupling could be due to: - prepulse - electron source divergence. ü Experiments on fast ignition show proton focusing spot is adequate for FI. However, conversion efficiency has to be increased. 2 Outline § Short Pulse High Intensity Laser Solid Interaction - New Frontiers § Extreme conditions with a short pulse laser § Applications § Fast Ignition - Progress - Current status § Summary Progress in laser technology 10 9 2000 Relativistic ions 8 Nonlinearity of 10 Vacuum ) Multi-GeV elecs. V 7 1990 Fast Ignition e 10 ( e +e- Production y 6 Weapons Physics g 10 Nuclear reactions r e 5 Relativistic -
Chapter 20 SOFT LASER DESORPTION IONIZATION - MALDI, DIOS and NANOSTRUCTURES
Chapter 20 SOFT LASER DESORPTION IONIZATION - MALDI, DIOS AND NANOSTRUCTURES Akos Veites Department of Chemistry, Institute for Proteomics Technology and Applications, The George Washington University, Washington DC 20052 1. INTRODUCTION In 1948, Ame Tiselius won the Nobel Prize in chemistry for the discovery of electrophoresis and its application to analyze large molecules, specifically complex serum proteins. During the following decades, gel electrophoresis and its derivative techniques became a central method for molecular biology. They allowed for the identification of molecular mass with an accuracy of ~1 kDa, i.e., a thousand atomic mass units. Although this method enabled the separation of thousands of proteins from biological samples, the determination of the actual molecular weight, and with it finding the true identity of many substances, remained unachievable. When it came to accurate mass determination of small molecules, mass spectrometry was the method of choice. However, for the accurate mass analysis of large molecules, their low volatility presented a fundamental obstacle. Typically, the larger the molecule, the harder it is to transfer it into the gas phase without degradation. Depositing the energy necessary for volatilization initiates other competing processes that elevate the internal energy of the adsorbate and results in its fragmentation. This competition between evaporation (or desorption) and fragmentation was recognized early on and the method of rapid heating was proposed to minimize the latter (Beuhler, et al., 1974). Lasers with submicrosecond pulse length were appealing tools for rapid heating but the initial results indicated limitations with respect to the ultimate size of the biomolecules (m/z < 1,500) that could 506 Laser Ablation and its Applications be successfully analyzed (Posthumus ,et al., 1978). -
Laser Ablationablation
LaserLaser AblationAblation FundamentalsFundamentals && ApplicationsApplications Samuel S. Mao Department of Mechanical Engineering Advanced Energy Technology Department University of California at Berkeley Lawrence Berkeley National Laboratory March 10, 2005 University of California at Berkeley Q Lawrence Berkeley National Laboratory LaserLaser AblationAblation What is “Laser Ablation”? Mass removal by coupling laser energy to a target material University of California at Berkeley Q Lawrence Berkeley National Laboratory ion lat ab er IsIs itit important?important? las ) Film deposition substrate * oxide/superconductor films material * nanocrystals/nanotubes plume target mass spectrometer ) Materials characterization * semiconductor doping profiling plasma lens * solid state chemical analysis target optical spectrometer ) Micro structuring * direct wave guide writing * 3D micro fabrication microstructure target transparent solid University of California at Berkeley Q Lawrence Berkeley National Laboratory ion lat ab er IsIs itit important?important? las ) Film deposition * oxide/superconductor films * nanocrystals/nanotubes ) Materials characterization * semiconductor doping profiling * solid state chemical analysis 100 µm ) Micro structuring * direct wave guide writing * 3D micro fabrication University of California at Berkeley Q Lawrence Berkeley National Laboratory ion lat ab er DoDo wewe reallyreally understand?understand? las laser beam “Laser ablation … is still largely unexplored at the plasma fundamental level.” J. C. Miller & -
RAPID COMMUNICATIONS Resonant Infrared Pulsed-Laser Deposition Of
RAPID COMMUNICATIONS This section is reserved for short submissions which contain important new results and are intended for accelerated publication. Resonant infrared pulsed-laser deposition of polymer films using a free-electron laser Daniel M. Bubb,a) J. S. Horwitz, J. H. Callahan, R. A. McGill, E. J. Houser, and D. B. Chrisey Naval Research Laboratory, Washington, DC 20375 M. R. Papantonakis and R. F. Haglund, Jr. Department of Physics and Astronomy and W. M. Keck Foundation Free-Electron Laser Center, Vanderbilt University, Nashville, Tennessee 37235 M. C. Galicia and A. Vertes Department of Chemistry, George Washington University, Washington, DC 20001 ͑Received 12 March 2001; accepted 29 May 2001͒ Thin films of polyethylene glycol ͑MW 1500͒ have been prepared by pulsed-laser deposition ͑PLD͒ using both a tunable infrared ͑ϭ2.9 m, 3.4 m͒ and an ultraviolet laser ͑ϭ193 nm͒.A comparison of the physicochemical properties of the films by means of Fourier transform infrared spectroscopy, electrospray ionization mass spectrometry, and matrix-assisted laser desorption and ionization shows that when the IR laser is tuned to a resonant absorption in the polymer, the IR PLD thin films are identical to the starting material, whereas the UV PLD show significant structural modification. These results are important for several biomedical applications of organic and polymeric thin films. © 2001 American Vacuum Society. ͓DOI: 10.1116/1.1387052͔ I. INTRODUCTION physical characteristics of the bulk PEG material, whereas Polyethylene glycol ͑PEG͒ is a technologically important the UV PLD deposited PEG materials do not. In addition, the polymer with many biomedical applications.1 Examples in- results also show clearly that the mechanism of IR PLD is clude tissue engineering,2 spatial patterning of cells,3,4 drug fundamentally different than UV PLD. -
MRI-Guided Laser Ablation Surgery for Epilepsy
MRI-Guided Laser Ablation Surgery for Epilepsy In August 2010, Texas Children’s Hospital became the first hospital in the world to use real-time MRI-guided thermal imaging and laser technology to destroy epilepsy-causing lesions in the brain that are too deep inside the brain to safely access with usual neurosurgical methods. To date, our team has performed more than 100 of these procedures on patients who have traveled to Houston and Texas Children’s from around the globe. This technology has become a standard of care and is now being used in many adult and pediatric centers across the United States. The advantages of the MRI-guided laser surgery procedure include: • A safer, significantly less-invasive alternative to open brain surgery with a craniotomy, which is the traditional technique used for the surgical treatment of epilepsy. • No hair is removed from the patient’s head. • Only a 3 mm opening is needed for the laser. It is closed with a single suture resulting in less scarring and pain for the patient. • A reduced risk of complications and a faster recovery time for the patient. Most patients are discharged the day after surgery. MRI-guided laser surgery is changing the face of epilepsy treatment and provides a life-altering option for many epilepsy surgery candidates. The benefits of this new approach in reducing risk and invasiveness may open the door for more epilepsy patients to see surgery as a viable treatment option. Epilepsy today • Approximately 1 in 10 people will have at least one seizure during their lifetime. -
Redalyc.Synthesis and Characterization of Linio2 Targets
Superficies y vacío ISSN: 1665-3521 [email protected] Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C. México López-Iturbe, J.; Camacho-López, M. A.; Escobar-Alarcón, L.; Camps, E. Synthesis and characterization of LiNiO2 targets for thin film deposition by pulsed laser ablation Superficies y vacío, vol. 18, núm. 4, diciembre, 2005, pp. 27-30 Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales A.C. Distrito Federal, México Available in: http://www.redalyc.org/articulo.oa?id=94218407 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Superficies y Vacío 18(4), 27-30, diciembre de 2005 ©Sociedad Mexicana de Ciencia y Tecnología de Superficies y Materiales Synthesis and characterization of LiNiO2 targets for thin film deposition by pulsed laser ablation J. López-Iturbe Posgrado en Ciencia de Materiales, Facultad de Química, Universidad Autónoma del Estado de México M.A. Camacho-López Facultad de Química-Universidad Autónoma del Estado de México Paseo Colón y Tollocan, C.P. 50130, Toluca, México L. Escobar-Alarcón, E. Camps Departamento de Física, Instituto Nacional de Investigaciones Nucleare Apartado Postal 18-1027, México DF 11801, México (Recibido: 26 de septiembre de 2005; Aceptado: 31 de octubre de 2005) In order to deposit LiNiO2 thin films by pulsed laser deposition (PLD), a LiNiO2 target was prepared by a solid-state reaction from NiO and Li2O. The effect of the Li2O wt. -
Phase Formation of Manganese Oxide Thin Films Using Pulsed Laser Deposition† Cite This: Mater
Materials Advances View Article Online PAPER View Journal | View Issue Phase formation of manganese oxide thin films using pulsed laser deposition† Cite this: Mater. Adv.,2021, 2,303 Lauren M. Garten, *‡ Praneetha Selvarasu, § John Perkins,¶ David Ginley and Andriy Zakutayev * Manganese oxides have enabled a wide range of technologies including oxygen evolution catalysts, lithium ion batteries, and thermochemical water splitting. However, the variable oxidation state and rich polymorphism of manganese oxides make it difficult to find the processing conditions to target a particular phase of manganese oxide. Targeted synthesis requires a more complete understanding of the phase space and the impact of multiple processing variables on phase formation. Here, we demonstrate the impact of substrate temperature, total deposition pressure, partial pressure of oxygen, and target composition on the phase formation of manganese oxides grown using combinatorial pulsed laser deposition (PLD). Thin films were deposited from a MnO, Mn2O3 or MnO2 target onto amorphous glass Creative Commons Attribution 3.0 Unported Licence. substrates with a continuously varied temperature provided by a combinatorial heater. A combination of X-ray diffraction, Rutherford backscattering spectroscopy, and Raman and Fourier transform infrared (FTIR) spectroscopies were used to determine the phases present in the samples. The oxygen partial pressure was found to be the critical factor determining phase formation, while the total pressure, target composition, and substrate temperature have smaller and more complex effects on phase formation. Received 15th June 2020, Comparing the results of this work to the published temperature–pressure phase diagrams shows that Accepted 20th October 2020 the PLD thin films vary significantly from the expected equilibrium phases of either the bulk materials DOI: 10.1039/d0ma00417k or nanoparticles.