DOCSLIB.ORG

Strain-Induced Semimetal-Metal Transition in Silicene

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Strain-Induced Semimetal-Metal Transition in Silicene OFFPRINT Strain-induced semimetal-metal transition in silicene G. Liu, M. S. Wu, C. Y. Ouyang and B. Xu EPL, 99 (2012) 17010 Please visit the new website www.epljournal.org A LETTERS JOURNAL EXPLORING THE FRONTIERS OF PHYSICS AN INVITATION TO SUBMIT YOUR WORK www.epljournal.org The Editorial Board invites you to submit your letters to EPL EPL is a leading international journal publishing original, high-quality Letters in all areas of physics, ranging from condensed matter topics and interdisciplinary research to astrophysics, geophysics, plasma and fusion sciences, including those with application potential. The high profile of the journal combined with the excellent scientific quality of the articles continue to ensure EPL is an essential resource for its worldwide audience. EPL offers authors global visibility and a great opportunity to share their work with others across the whole of the physics community. Run by active scientists, for scientists EPL is reviewed by scientists for scientists, to serve and support the international scientific community. The Editorial Board is a team of active research scientists with an expert understanding of the needs of both authors and researchers. * IMPACT FACTOR 2.753*As ranked by ISI 2010 www.epljournal.org A LETTERS JOURNAL EXPLORING www.epljournal.org THE FRONTIERS OF PHYSICS IMPACT FACTOR Six good reasons to publish with EPL * We want to work with you to help gain recognition for your high-quality work through 2.753 worldwide visibility and high citations. * As listed in the ISI® 2010 Science Citation Index Journal Citation Reports Quality – The 40+ Co-Editors, who are experts in their fields, oversee the 1 entire peer-review process, from selection of the referees to making all final OVER acceptance decisions 500 000 Impact Factor – The 2010 Impact Factor is 2.753; your work will be in the full text downloads in 2010 2 right place to be cited by your peers 3 Speed of processing – We aim to provide you with a quick and efficient 30 DAYS service; the median time from acceptance to online publication is 30 days average receipt to online publication in 2010 4 High visibility – All articles are free to read for 30 days from online publication date 5 International reach – Over 2,000 institutions have access to EPL, 16 961 enabling your work to be read by your peers in 100 countries citations in 2010 37% increase from 2007 Open Access – Articles are offered open access for a one-off author 6 payment “We’ve had a very positive experience with EPL, and Details on preparing, submitting and tracking the progress of your manuscript not only on this occasion. from submission to acceptance are available on the EPL submission website The fact that one can www.epletters.net. identify an appropriate editor, and the editor If you would like further information about our author service or EPL in general, is an active scientist in please visit www.epljournal.org or e-mail us at [email protected]. the field, makes a huge difference.” Dr. Ivar Martinv Los Alamos National Laboratory, EPL is published in partnership with: USA European Physical Society Società Italiana di Fisica EDP Sciences IOP Publishing www.epljournal.org A LETTERS JOURNAL EXPLORING THE FRONTIERS OF PHYSICS EPL Compilation Index www.epljournal.org Visit the EPL website to read the latest articles published in cutting-edge fields of research from across the whole of physics. Each compilation is led by its own Co-Editor, who is a leading scientist in that field, and who is responsible for overseeing the review process, selecting referees and making publication decisions for every manuscript. • Graphene Biaxial strain on lens-shaped quantum rings of different inner radii, adapted from Zhang et al 2008 EPL 83 67004. • Liquid Crystals • High Transition Temperature Superconductors • Quantum Information Processing & Communication • Biological & Soft Matter Physics • Atomic, Molecular & Optical Physics • Bose–Einstein Condensates & Ultracold Gases • Metamaterials, Nanostructures & Magnetic Materials • Mathematical Methods • Physics of Gases, Plasmas & Electric Fields Artistic impression of electrostatic particle–particle • High Energy Nuclear Physics interactions in dielectrophoresis, adapted from N Aubry and P Singh 2006 EPL 74 623. If you are working on research in any of these areas, the Co-Editors would be delighted to receive your submission. Articles should be submitted via the automated manuscript system at www.epletters.net If you would like further information about our author service or EPL in general, please visit www.epljournal.org or e-mail us at [email protected] Artistic impression of velocity and normal stress profiles around a sphere that moves through a polymer solution, adapted from R Tuinier, J K G Dhont and T-H Fan 2006 EPL 75 929. Image: Ornamental multiplication of space-time figures of temperature transformation rules (adapted from T. S. Bíró and P. Ván 2010 EPL 89 30001; artistic impression by Frédérique Swist). July 2012 EPL, 99 (2012) 17010 www.epljournal.org doi: 10.1209/0295-5075/99/17010 Strain-induced semimetal-metal transition in silicene G. Liu, M. S. Wu, C. Y. Ouyang and B. Xu(a) College of Physics and Communication Electronics, Jiangxi Normal University - Nanchang, Jiangxi, 330022, PRC received 16 April 2012; accepted in final form 19 June 2012 published online 11 July 2012 PACS 73.22.-f – Electronic structure of nanoscale materials and related systems PACS 71.15.Mb – Density functional theory, local density approximation, gradient and other corrections Abstract – The effect of the tensile strain on the electronic structure of the silicene is studied by using first-principles density functional theory. It is found that a semimetal-metal transition occurs when an in-plane strain larger than 7.5% is applied in silicene. The downward movement of the lowest conduction band at Γ-point, which originates from the weakened interaction between neighboring Si atoms, leads to the transition. The proposed mechanical control of the electronic properties will widen the application of the silicene in Si-based nanotechnology. Copyright c EPLA, 2012 Silicene, a two-dimensional (2D) monolayer honeycomb field [21]. If the semimetal-metal transition can be real- structure of silicon atoms, has recently attracted intensive ized, the potential applications of silicene will be wider in attention from the scientific community [1–12]. Compared the future nanotechnology. with graphene, the hottest 2D materials in the past several In this letter, we study the response of silicene under years, silicene could have more potential application in the the biaxial tensile strain. The transition from semimetal future Si-based nanotechnology, because they could enable to metal is predicted in silicene when the strain is beyond the electronics industry to produce fast nanoscale elec- 7.5%. Energy band structures reveal that the transition tronics without retooling to use carbon instead of silicon. results from the downward shift of the lowest conduction Experimentally, Nakano et al. reported the synthesis of band at Γ-point as increasing the strain. Further analysis silicene via the chemical exfoliation of CaSi2 [13]. Recently, of partial charge density shows that the downward shift of the possible growth of silicene nanoribbon on Ag (100) the lowest conduction band is related to the weakening of or Ag (110) substrates has been reported [14–17]. Since the π∗ bond due to the increase of the Si-Si bond length. silicon prefers sp3 hybridization instead of sp2, silicene All calculations were performed using the Vienna ab is energetically favorable as a low-buckled (LB) struc- initio simulation package (VASP) code, and adopting ture [18,19]. More interestingly, theoretical calculations the projector augmented-wave (PAW) potentials [22] on silicene show that the π and π∗ bands linearly cross and Perdew-Burke-Ernzerhof (PBE) generalized gradient at the Fermi level, reflecting the semimetallic or zero- approximation (GGA) exchange correlation functional gap semiconducting character of silicene [18,19]. Similar [23]. The energy cutoff for expansion of wave functions to graphene, therefore, it is important to modify a silicene and potentials is 550 eV. Monkhorst-Pack special k-point sheet in order to tailor its properties. For example, hydro- method [24] was used with a grid of 40 × 40 × 1. The genation of silicene can open a gap [3,7]. By using ab initio entire systems were relaxed by conjugate gradient method calculations, Ni et al. predicted that a vertical electric until the force on each atom is less than 0.001 eV/A.˚ The field is able to open a band gap in semimetallic single- 1 × 1 unit cell was employed in our calculations. We set layer buckled silicene [20]. They also found that the size up a vacuum region of 11.76 A˚ along the direction vertical of the band gap can be linearly tuned by the intensity of to the silicene layer to avoid the interaction between two the electric field. Though many efforts have been focused adjacent images. on the transition from semimetal to semiconductor for The relaxed structure of silicene is shown in fig. 1. The silicene, the study related to its change from semimetal optimized lattice parameter a is 3.86 A,˚ in agreement with to metal is not available in the literature except for the previous results (a =3.86 A)˚ [25]. The Si-Si bond length case subjected to a sufficiently high transverse electric is calculated to be 2.27 A,˚ showing a contraction of the bond compared with bulk Si. The buckling parameter Δ (a)E-mail: [email protected] (as shown in fig. 1(a)) is 0.46 A,˚ also consistent with other 17010-p1 G. Liu et al. without strain present the semimetallic character, with π and π∗ bands both crossing the Fermi level at the K-point, as shown in fig.
Load more

Recommended publications
  • Silicene, Silicene Derivatives, and Their Device Applications
    Chemical Society Reviews Silicene, silicene derivatives, and their device applications Journal: Chemical Society Reviews Manuscript ID CS-REV-04-2018-000338.R1 Article Type: Review Article Date Submitted by the Author: 27-Jun-2018 Complete List of Authors: Molle, Alessandro; CNR-IMM, unit of Agrate Brianza Grazianetti, Carlo; CNR-IMM, unit of Agrate Brianza Tao, Li; The University of Texas at Autin, Microelectronics Research Center Taneja, Deepyanti; The University of Texas at Autin, Microelectronics Research Center Alam, Md Hasibul; The University of Texas at Autin, Microelectronics Research Center Akinwande, Deji; The University of Texas at Autin, Microelectronics Research Center Page 1 of 17 PleaseChemical do not Society adjust Reviews margins Chemical Society Reviews REVIEW Silicene, silicene derivatives, and their device applications Alessandro Molle,a Carlo Grazianetti,a,† Li Tao,b,† Deepyanti Taneja,c Md. Hasibul Alam,c and Deji c,† Received 00th January 20xx, Akinwande Accepted 00th January 20xx Silicene, the ultimate scaling of silicon atomic sheet in a buckled honeycomb lattice, represents a monoelemental class of DOI: 10.1039/x0xx00000x two-dimensional (2D) materials similar to graphene but with unique potential for a host of exotic electronic properties. www.rsc.org/ Nonetheless, there is a lack of experimental studies largely due to the interplay between material degradation and process portability issues. This Review highlights state-of-the-art experimental progress and future opportunities in synthesis, characterization, stabilization, processing and experimental device example of monolayer silicene and thicker derivatives. Electrostatic characteristics of Ag-removal silicene field-effect transistor exihibits ambipolar charge transport, corroborating with theoretical predictions on Dirac Fermions and Dirac cone in band structure.
    [Show full text]
  • Quantum Mechanics Electromotive Force
    Quantum Mechanics_Electromotive force . Electromotive force, also called emf[1] (denoted and measured in volts), is the voltage developed by any source of electrical energy such as a batteryor dynamo.[2] The word "force" in this case is not used to mean mechanical force, measured in newtons, but a potential, or energy per unit of charge, measured involts. In electromagnetic induction, emf can be defined around a closed loop as the electromagnetic workthat would be transferred to a unit of charge if it travels once around that loop.[3] (While the charge travels around the loop, it can simultaneously lose the energy via resistance into thermal energy.) For a time-varying magnetic flux impinging a loop, theElectric potential scalar field is not defined due to circulating electric vector field, but nevertheless an emf does work that can be measured as a virtual electric potential around that loop.[4] In a two-terminal device (such as an electrochemical cell or electromagnetic generator), the emf can be measured as the open-circuit potential difference across the two terminals. The potential difference thus created drives current flow if an external circuit is attached to the source of emf. When current flows, however, the potential difference across the terminals is no longer equal to the emf, but will be smaller because of the voltage drop within the device due to its internal resistance. Devices that can provide emf includeelectrochemical cells, thermoelectric devices, solar cells and photodiodes, electrical generators,transformers, and even Van de Graaff generators.[4][5] In nature, emf is generated whenever magnetic field fluctuations occur through a surface.
    [Show full text]
  • Novel Electronic Properties of Monoclinic
    www.nature.com/scientificreports OPEN Novel electronic properties of monoclinic M P4 (M = Cr, Mo, W) compounds with or without topological nodal line Muhammad Rizwan Khan1,2, Kun Bu1,2, Jun‑Shuai Chai1,2 & Jian‑Tao Wang1,2,3* Transition metal phosphides hold novel metallic, semimetallic, and semiconducting behaviors. Here we report by ab initio calculations a systematical study on the structural and electronic properties of 6 MP4 (M = Cr, Mo, W) phosphides in monoclinic C2/c (C 2h ) symmetry. Their dynamical stabilities have been confrmed by phonon modes calculations. Detailed analysis of the electronic band structures and density of states reveal that CrP4 is a semiconductor with an indirect band gap of 0.47 eV in association with the p orbital of P atoms, while MoP4 is a Dirac semimetal with an isolated nodal point at the Ŵ point and WP4 is a topological nodal line semimetal with a closed nodal ring inside the frst Brillouin zone relative to the d orbital of Mo and W atoms, respectively. Comparison of the phosphides with group VB, VIB and VIIB transition metals shows a trend of change from metallic to semiconducting behavior from VB-MP4 to VIIB-MP4 compounds. These results provide a systematical understandings on the distinct electronic properties of these compounds. Transition metal phosphides (TMPs) have been attracted considerable research interest due to their structural and compositional diversity that results in a broad range of novel electronic, magnetic and catalytic properties1–4. Tis family consists of large number of materials, having distinct crystallographic structures and morpholo- gies because of choices of diferent TMs and phosphorus atoms 5.
    [Show full text]
  • Call for Papers | 2022 MRS Spring Meeting
    Symposium CH01: Frontiers of In Situ Materials Characterization—From New Instrumentation and Method to Imaging Aided Materials Design Advancement in synchrotron X-ray techniques, microscopy and spectroscopy has extended the characterization capability to study the structure, phonon, spin, and electromagnetic field of materials with improved temporal and spatial resolution. This symposium will cover recent advances of in situ imaging techniques and highlight progress in materials design, synthesis, and engineering in catalysts and devices aided by insights gained from the state-of-the-art real-time materials characterization. This program will bring together works with an emphasis on developing and applying new methods in X-ray or electron diffraction, scanning probe microscopy, and other techniques to in situ studies of the dynamics in materials, such as the structural and chemical evolution of energy materials and catalysts, and the electronic structure of semiconductor and functional oxides. Additionally, this symposium will focus on works in designing, synthesizing new materials and optimizing materials properties by utilizing the insights on mechanisms of materials processes at different length or time scales revealed by in situ techniques. Emerging big data analysis approaches and method development presenting opportunities to aid materials design are welcomed. Discussion on experimental strategies, data analysis, and conceptual works showcasing how new in situ tools can probe exotic and critical processes in materials, such as charge and heat transfer, bonding, transport of molecule and ions, are encouraged. The symposium will identify new directions of in situ research, facilitate the application of new techniques to in situ liquid and gas phase microscopy and spectroscopy, and bridge mechanistic study with practical synthesis and engineering for materials with a broad range of applications.
    [Show full text]
  • Hear the Sound of Weyl Fermions
    PHYSICAL REVIEW X 9, 021053 (2019) Featured in Physics Hear the Sound of Weyl Fermions Zhida Song1,2 and Xi Dai1,* 1Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 2Department of Physics, Princeton University, Princeton, New Jersey 08544, USA (Received 4 February 2019; revised manuscript received 10 April 2019; published 17 June 2019) Quasiparticles and collective modes are two fundamental aspects that characterize quantum matter in addition to its ground-state features. For example, the low-energy physics for Fermi-liquid phase in He-III is featured not only by fermionic quasiparticles near the chemical potential but also by fruitful collective modes in the long-wave limit, including several different sound waves that can propagate through it under different circumstances. On the other hand, it is very difficult for sound waves to be carried by electron liquid in ordinary metals due to the fact that long-range Coulomb interaction among electrons will generate a plasmon gap for ordinary electron density oscillation and thus prohibits the propagation of sound waves through it. In the present paper, we propose a unique type of acoustic collective mode in Weyl semimetals under magnetic field called chiral zero sound. Chiral zero sound can be stabilized under the so-called “chiral limit,” where the intravalley scattering time is much shorter than the intervalley one and propagates only along an external magnetic field for Weyl semimetals with multiple pairs of Weyl points. The sound velocity of chiral zero sound is proportional to the field strength in the weak field limit, whereas it oscillates dramatically in the strong field limit, generating an entirely new mechanism for quantum oscillations through the dynamics of neutral bosonic excitation, which may manifest itself in the thermal conductivity measurements under magnetic field.
    [Show full text]
  • Chapter 4: Bonding in Solids and Electronic Properties
    Chapter 4: Bonding in Solids and Electronic Properties Free electron theory Consider free electrons in a metal – an electron gas. •regards a metal as a box in which electrons are free to move. •assumes nuclei stay fixed on their lattice sites surrounded by core electrons, while the valence electrons move freely through the solid. •Ignoring the core electrons, one can treat the outer electrons with a quantum mechanical description. •Taking just one electron, the problem is reduced to a particle in a box. Electron is confined to a line of length a. Schrodinger equation 2 2 2 d d 2me E 2 (E V ) 2 2 2me dx dx Electron is not allowed outside the box, so the potential is ∞ outside the box. Energy is quantized, with quantum numbers n. 2 2 2 n2h2 h2 n n n In 1d: E In 3d: E a b c 2 8m a2 b2 c2 8mea e 1 2 2 2 2 Each set of quantum numbers n , n , h n n n a b a b c E 2 2 2 and nc will give rise to an energy level. 8me a b c •In three dimensions, there are multiple combination of energy levels that will give the same energy, whereas in one-dimension n and –n are equal in energy. 2 2 2 2 2 2 na/a nb/b nc/c na /a + nb /b + nc /c 6 6 6 108 The number of states with the 2 2 10 108 same energy is known as the degeneracy. 2 10 2 108 10 2 2 108 When dealing with a crystal with ~1020 atoms, it becomes difficult to work out all the possible combinations.
    [Show full text]
  • Application of Silicene, Germanene and Stanene for Na Or Li Ion Storage: a Theoretical Investigation
    Application of silicene, germanene and stanene for Na or Li ion storage: A theoretical investigation Bohayra Mortazavi*,1, Arezoo Dianat2, Gianaurelio Cuniberti2, Timon Rabczuk1,# 1Institute of Structural Mechanics, Bauhaus-Universität Weimar, Marienstr. 15, D-99423 Weimar, Germany. 2Institute for Materials Science and Max Bergman Center of Biomaterials, TU Dresden, 01062 Dresden, Germany Abstract Silicene, germanene and stanene likely to graphene are atomic thick material with interesting properties. We employed first-principles density functional theory (DFT) calculations to investigate and compare the interaction of Na or Li ions on these films. We first identified the most stable binding sites and their corresponding binding energies for a single Na or Li adatom on the considered membranes. Then we gradually increased the ions concentration until the full saturation of the surfaces is achieved. Our Bader charge analysis confirmed complete charge transfer between Li or Na ions with the studied 2D sheets. We then utilized nudged elastic band method to analyze and compare the energy barriers for Li or Na ions diffusions along the surface and through the films thicknesses. Our investigation findings can be useful for the potential application of silicene, germanene and stanene for Na or Li ion batteries. Keywords: Silicene; germanene; stanene; first-principles; Li ions; *Corresponding author (Bohayra Mortazavi): [email protected] Tel: +49 157 8037 8770, Fax: +49 364 358 4511 #[email protected] 1. Introduction The interest toward two-dimensional (2D) materials was raised by the great success of graphene [1–3]. Graphene is a zero-gap semiconductor that present outstanding mechanical [4] and heat conduction [5] properties, surpassing all known materials.
    [Show full text]
  • Lecture 24. Degenerate Fermi Gas (Ch
    Lecture 24. Degenerate Fermi Gas (Ch. 7) We will consider the gas of fermions in the degenerate regime, where the density n exceeds by far the quantum density nQ, or, in terms of energies, where the Fermi energy exceeds by far the temperature. We have seen that for such a gas μ is positive, and we’ll confine our attention to the limit in which μ is close to its T=0 value, the Fermi energy EF. ~ kBT μ/EF 1 1 kBT/EF occupancy T=0 (with respect to E ) F The most important degenerate Fermi gas is 1 the electron gas in metals and in white dwarf nε()(),, T= f ε T = stars. Another case is the neutron star, whose ε⎛ − μ⎞ exp⎜ ⎟ +1 density is so high that the neutron gas is ⎝kB T⎠ degenerate. Degenerate Fermi Gas in Metals empty states ε We consider the mobile electrons in the conduction EF conduction band which can participate in the charge transport. The band energy is measured from the bottom of the conduction 0 band. When the metal atoms are brought together, valence their outer electrons break away and can move freely band through the solid. In good metals with the concentration ~ 1 electron/ion, the density of electrons in the electron states electron states conduction band n ~ 1 electron per (0.2 nm)3 ~ 1029 in an isolated in metal electrons/m3 . atom The electrons are prevented from escaping from the metal by the net Coulomb attraction to the positive ions; the energy required for an electron to escape (the work function) is typically a few eV.
    [Show full text]
  • Chapter 13 Ideal Fermi
    Chapter 13 Ideal Fermi gas The properties of an ideal Fermi gas are strongly determined by the Pauli principle. We shall consider the limit: k T µ,βµ 1, B � � which defines the degenerate Fermi gas. In this limit, the quantum mechanical nature of the system becomes especially important, and the system has little to do with the classical ideal gas. Since this chapter is devoted to fermions, we shall omit in the following the subscript ( ) that we used for the fermionic statistical quantities in the previous chapter. − 13.1 Equation of state Consider a gas ofN non-interacting fermions, e.g., electrons, whose one-particle wave- functionsϕ r(�r) are plane-waves. In this case, a complete set of quantum numbersr is given, for instance, by the three cartesian components of the wave vector �k and thez spin projectionm s of an electron: r (k , k , k , m ). ≡ x y z s Spin-independent Hamiltonians. We will consider only spin independent Hamiltonian operator of the type ˆ 3 H= �k ck† ck + d r V(r)c r†cr , �k � where thefirst and the second terms are respectively the kinetic and th potential energy. The summation over the statesr (whenever it has to be performed) can then be reduced to the summation over states with different wavevectork(p=¯hk): ... (2s + 1) ..., ⇒ r � �k where the summation over the spin quantum numberm s = s, s+1, . , s has been taken into account by the prefactor (2s + 1). − − 159 160 CHAPTER 13. IDEAL FERMI GAS Wavefunctions in a box. We as- sume that the electrons are in a vol- ume defined by a cube with sidesL x, Ly,L z and volumeV=L xLyLz.
    [Show full text]
  • Theoretical Study of a New Porous 2D Silicon-Filled Composite Based on Graphene and Single-Walled Carbon Nanotubes for Lithium-Ion Batteries
    applied sciences Article Theoretical Study of a New Porous 2D Silicon-Filled Composite Based on Graphene and Single-Walled Carbon Nanotubes for Lithium-Ion Batteries Dmitry A. Kolosov 1 and Olga E. Glukhova 1,2,* 1 Department of Physics, Saratov State University, Astrakhanskaya street 83, 410012 Saratov, Russia; [email protected] 2 Laboratory of Biomedical Nanotechnology, I.M. Sechenov First Moscow State Medical University, Trubetskaya street 8-2, 119991 Moscow, Russia * Correspondence: [email protected]; Tel.: +7-84-5251-4562 Received: 24 July 2020; Accepted: 18 August 2020; Published: 21 August 2020 Abstract: The incorporation of Si16 nanoclusters into the pores of pillared graphene on the base of single-walled carbon nanotubes (SWCNTs) significantly improved its properties as anode material of Li-ion batteries. Quantum-chemical calculation of the silicon-filled pillared graphene efficiency found (I) the optimal mass fraction of silicon (Si)providing maximum anode capacity; (II) the optimal Li: C and Li: Si ratios, when a smaller number of C and Si atoms captured more amount of Li ions; and (III) the conditions of the most energetically favorable delithiation process. For 2D-pillared graphene with a sheet spacing of 2–3 nm and SWCNTs distance of ~5 nm the best silicon concentration in pores was ~13–18 wt.%. In this case the value of achieved capacity exceeded the graphite anode one by 400%. Increasing of silicon mass fraction to 35–44% or more leads to a decrease in the anode capacity and to a risk of pillared graphene destruction. It is predicted that this study will provide useful information for the design of hybrid silicon-carbon anodes for efficient next-generation Li-ion batteries.
    [Show full text]
  • Evidence of Silicene in Honeycomb Structures of Silicon on Ag(111)
    Letter pubs.acs.org/NanoLett Evidence of Silicene in Honeycomb Structures of Silicon on Ag(111) † † † ‡ † † † † Baojie Feng, Zijing Ding, Sheng Meng, Yugui Yao, , Xiaoyue He, Peng Cheng, Lan Chen,*, † and Kehui Wu*, † Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China ‡ School of Physics, Beijing Institute of Technology, Beijing 100081, China ABSTRACT: In the search for evidence of silicene, a two- dimensional honeycomb lattice of silicon, it is important to obtain a complete picture for the evolution of Si structures on Ag(111), which is believed to be the most suitable substrate for growth of silicene so far. In this work we report the finding and evolution of several monolayer superstructures of silicon on Ag(111), depend- ing on the coverage and temperature. Combined with first- principles calculations, the detailed structures of these phases have been illuminated. These structures were found to share common building blocks of silicon rings, and they evolve from a fragment of silicene to a complete monolayer silicene and multilayer silicene. Our results elucidate how silicene forms on Ag(111) surface and provides methods to synthesize high-quality and large- scale silicene. KEYWORDS: Silicene, Ag(111), scannning tunneling microscopy, molecular beam epitaxy, first-principles calculation ith the development of the semiconductor industry of silicene and optimizing the preparation procedure for W toward a smaller scale, the rich quantum phenomena in growing high-quality silicene films, it is important to build a low-dimensional systems may lead to new concepts and complete understanding of the formation mechanism and ground-breaking applications. In the past decade graphene growth dynamics of possible silicon structures on Ag(111), has emerged as a low-dimensional system for both fundamental which is currently believed to be the best substrate for growing research and novel applications including electronic devices, silicene.
    [Show full text]
  • Nonsaturating Large Magnetoresistance in Semimetals
    This document is downloaded from DR‑NTU (https://dr.ntu.edu.sg) Nanyang Technological University, Singapore. Nonsaturating large magnetoresistance in semimetals Leahy, Ian A.; Lin, Yu‑Ping; Siegfried, Peter E.; Treglia, Andrew C.; Song, Justin Chien Wen; Nandkishore, Rahul M.; Lee, Minhyea 2018 Leahy, I. A., Lin, Y.‑P., Siegfried, P. E., Treglia, A. C., Song, J. C. W., Nandkishore, R. M., & Lee, M. (2018). Nonsaturating large magnetoresistance in semimeta. Proceedings of the National Academy of Sciences of the United States of America, 115 (42), 10570‑10575. doi:10.1073/pnas.1808747115 https://hdl.handle.net/10356/137998 https://doi.org/10.1073/pnas.1808747115 © 2018 The Author(s). All rights reserved. This paper was published by National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America and is made available with permission of The Author(s). Downloaded on 01 Oct 2021 03:16:44 SGT Non-saturating large magnetoresistance in semimetals Ian A. Leahy,1 Yu-Ping Lin,1 Peter E. Siegfried,1 Andrew C. Treglia,1 Justin C. W. Song,2 Rahul M. Nandkishore,1, 3 and Minhyea Lee1, 4, ∗ 1Department of Physics, University of Colorado, Boulder, CO 80309, USA 2Division of Physics and Applied Physics, Nanyang Technological University, Singapore 637371 3Center for Theory of Quantum Matter, University of Colorado, Boulder, CO 80309, USA 4Center for Experiments on Quantum Materials, University of Colorado, Boulder, CO 80309, USA (Dated: September 6, 2018) The rapidly expanding class of quantum materials known as topological semimetals (TSM) dis- play unique transport properties, including a striking dependence of resistivity on applied magnetic field, that are of great interest for both scientific and technological reasons.
    [Show full text]