toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author (up) Xu, B.; Milošević, M.V.; Peeters, F.M. url  doi
openurl 
  Title Second-order multiple-quanta flux entry into a perforated spherical mesoscopic superconductor Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 21 Pages 214501-214501,7  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Flux entry in type-II superconductors without prominent symmetry is a first-order phase transition, where flux enters conventionally gradual in units of a flux quantum. Here we show that neither is necessarily the case in a mesoscopic superconducting sphere with a perforation. In axially applied magnetic field, vortices initially occupy the hole, and can oppose further flux entry in the sample. As a result, multiple-quanta flux entry is found at significantly higher field, and it can manifest as a second-order transition due to suppressed geometric barrier at the equatorial belt of the sample. At high fields a new state is found, with gradually destroyed condensate from the equator inwards, the exact opposite of surface superconductivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000286737800007 Publication Date 2010-12-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 2 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-V1), the Belgian Science Policy (IAP), and the ESF “Nanoscience and Engineering in Superconductivity” program. ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:88039 Serial 2957  
Permanent link to this record
 

 
Author (up) Xu, B.; Milošević, M.V.; Peeters, F.M. url  doi
openurl 
  Title Vortex matter in oblate mesoscopic superconductors with a hole: broken symmetry vortex states and multi-vortex entry Type A1 Journal article
  Year 2009 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 11 Issue Pages 013020,1-013020,21  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using three-dimensional (3D) numerical discretization of the GinzburgLandau (GL) equations, we investigate the superconducting state of a sphere with a piercing hole in the presence of a magnetic field. In the case of samples with central perforation, in axially applied homogeneous magnetic field, we realized unconventional vortex states of broken symmetry due to complex, 3D competing interactions, which depend on the GL parameter ê. For certain sizes of the sample, non-hysteretic multi-vortex entry and exit is predicted with the non-existence of some vorticities as stable states. In a tilted magnetic field, we studied the gradual transformation of 3D flux patterns into 1D vortex chains, where vortices align along the perforation, and the evolvement of the multi-vortex entry as well. We analyze the flux-guiding ability of the hole in a tilted field, which leads to fractional flux response in magnetization M(H) curves.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000262932500003 Publication Date 2009-01-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 8 Open Access  
  Notes Approved Most recent IF: 3.786; 2009 IF: 3.312  
  Call Number UA @ lucian @ c:irua:75986 Serial 3873  
Permanent link to this record
 

 
Author (up) Xu, P.; Neek-Amal, M.; Barber, S.D.; Schoelz, J.K.; Ackerman, M.L.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M. doi  openurl
  Title Unusual ultra-low-frequency fluctuations in freestanding graphene Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 3720  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Intrinsic ripples in freestanding graphene have been exceedingly difficult to study. Individual ripple geometry was recently imaged using scanning tunnelling microscopy, but these measurements are limited to static configurations. Thermally-activated flexural phonon modes should generate dynamic changes in curvature. Here we show how to track the vertical movement of a one-square-angstrom region of freestanding graphene using scanning tunnelling microscopy, thereby allowing measurement of the out-of-plane time trajectory and fluctuations over long time periods. We also present a model from elasticity theory to explain the very-low-frequency oscillations. Unexpectedly, we sometimes detect a sudden colossal jump, which we interpret as due to mirror buckling. This innovative technique provides a much needed atomic-scale probe for the time-dependent behaviours of intrinsic ripples. The discovery of this novel progenitor represents a fundamental advance in the use of scanning tunnelling microscopy, which together with the application of a thermal load provides a low-frequency nano-resonator.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000335223200007 Publication Date 2014-04-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 62 Open Access  
  Notes ; This work was financially supported, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Euro-GRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:117201 Serial 3819  
Permanent link to this record
 

 
Author (up) Xu, W.; Dong, H.M.; Li, L.L.; Yao, J.Q.; Vasilopoulos, P.; Peeters, F.M. url  doi
openurl 
  Title Optoelectronic properties of graphene in the presence of optical phonon scattering Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 82 Issue 12 Pages 125304-125304,9  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000281516500009 Publication Date 2010-09-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 28 Open Access  
  Notes ; This work was supported by the Chinese Academy of Sciences, National Natural Science Foundation of China, and Department of Science and Technology of Yunnan Province. ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:84260 Serial 2496  
Permanent link to this record
 

 
Author (up) Xu, W.; Leadley, D.R.; Peeters, F.M.; Devreese, J.T.; Nicholas, R.J.; Harris, J.J.; Foxon, C.T. openurl 
  Title Destruction of magnetophonon resonance in high mobility heterojunctions from competition between elastic and inelastic scattering Type P3 Proceeding
  Year 1994 Publication Proceedings of the International Conference on the Physics of Semiconductors Abbreviated Journal  
  Volume 22 Issue Pages 839-842  
  Keywords P3 Proceeding; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:9284 Serial 665  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T. openurl 
  Title Diffusion-to-streaming transition in a two-dimensional electron system in a polar semiconductor Type A1 Journal article
  Year 1991 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 43 Issue Pages 14134-14141  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1991FQ97400035 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.736 Times cited 24 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:913 Serial 701  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T. url  doi
openurl 
  Title Electrophonon resonances in a quasi-two-dimensional electron system Type A1 Journal article
  Year 1993 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 48 Issue 3 Pages 1562-1570  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract When the energy difference between two electric subbands in a quasi-two-dimensional electron system equals a LO-phonon energy, resonant scattering will occur. This leads to an enhancement of the scattering rate and, consequently, to a suppression of the conductivity. Changing the energy difference between the electric subbands (e.g., through a gate) leads to a series of electrophonon resonances in the conductivity. A detailed study is made of this effect for different confinement potentials. We found that the scattering processes where the emission of a phonon is involved are very important for the electrophonon resonance and that the size of the effect decreases with increasing temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1993LP05000024 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.736 Times cited 45 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:5747 Serial 1022  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T. openurl 
  Title The hot electron distribution of two-dimensional electrons in a polar semiconductor at zero temperature Type A3 Journal article
  Year 1991 Publication Journal of physics: C: condensed matter Abbreviated Journal  
  Volume 3 Issue Pages 1783-1791  
  Keywords A3 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1991FE35700009 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 1 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:948 Serial 1490  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T. url  doi
openurl 
  Title Normal and hot electro-phonon resonance effect in a quasi-two-dimensional semiconductor system Type A1 Journal article
  Year 1993 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 5 Issue 15 Pages 2307-2320  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract The electro-phonon resonance effect is a consequence of a resonant interaction between two electric subbands mediated by an optical phonon. It occurs in a quasi-two-dimensional electron system each time the energy difference between two electric subbands equals the energy of a Lo phonon. We study the influence of this effect on the electron mobility by using the momentum balance equation. The temperature and electron density dependences of the resonances are studied in the linear and non-linear response regimes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos A1993KX70100004 Publication Date 2002-08-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.346 Times cited 18 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:102984 Serial 2367  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T. url  doi
openurl 
  Title Streaming-to-accumulation transition in a 2-dimensional electron-system in a polar semiconductor Type A1 Journal article
  Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 46 Issue 12 Pages 7571-7580  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract Hot-electron transport is studied for a two-dimensional electron gas coupled to longitudinal-optical phonons in crossed electric and magnetic fields. At low electric and high magnetic fields the electrons are accumulated, while at high electric fields they are in a streaming state. We develop a streaming-to-accumulation transition model and compare the results with that from a Monte Carlo simulation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1992JQ37800028 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.736 Times cited 13 Open Access  
  Notes Approved PHYSICS, APPLIED 28/145 Q1 #  
  Call Number UA @ lucian @ c:irua:103023 Serial 3174  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T. openurl 
  Title Warm-electron transport in a two-dimensional semiconductor Type A1 Journal article
  Year 1992 Publication Semiconductor science and technology Abbreviated Journal Semicond Sci Tech  
  Volume 7 Issue Pages 1251-1256  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos A1992JT73000006 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0268-1242 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.19 Times cited 3 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:2915 Serial 3903  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Devreese, J.T.; Leadley, D.R.; Nicholas, R.J. doi  openurl
  Title Destruction of magnetophonon resonance in high magnetic fields from impurity and phonon scattering in heterojunctions Type A1 Journal article
  Year 1996 Publication International journal of modern physics: B: condensed matter physics, statistical physics, applied physics Abbreviated Journal Int J Mod Phys B  
  Volume 10 Issue Pages 169-202  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Singapore Editor  
  Language Wos A1996TR56200002 Publication Date 2004-10-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0217-9792;1793-6578; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 0.937 Times cited 11 Open Access  
  Notes Approved CHEMISTRY, PHYSICAL 54/144 Q2 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 9/35 Q2 #  
  Call Number UA @ lucian @ c:irua:15803 Serial 664  
Permanent link to this record
 

 
Author (up) Xu, W.; Peeters, F.M.; Lu, T.C. url  doi
openurl 
  Title Dependence of resistivity on electron density and temperature in graphene Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 7 Pages 073403,1-073403,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract On the basis of the momentum-balance equation derived from the Boltzmann equation in which electron interactions with impurities and acoustic and optic phonons are included, we examine the dependence of the resistivity in graphene on temperature and electron density. Simple analytical expressions for the different contributions to the resistivity are obtained. Our results reproduce recent experimental findings and we are able to understand the different temperature dependence of the resistivity for low and high density samples.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000263815800013 Publication Date 2009-02-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 31 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:76222 Serial 642  
Permanent link to this record
 

 
Author (up) Xu, W.; Vasilopoulos, P.; Das, M.P.; Peeters, F.M. openurl 
  Title The low-temperature self-consistent g factor for heterostructures in strong magnetic fields Type A1 Journal article
  Year 1995 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 7 Issue Pages 4419-4432  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos A1995RC23600011 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.346 Times cited 20 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:12196 Serial 1853  
Permanent link to this record
 

 
Author (up) Xu, W.; Vasilopoulos, P.; Das, M.P.; Peeters, F.M. openurl 
  Title Self-consistent g* factor and spin-split Landau levels in strong magnetic fields and at low temperatures Type P3 Proceeding
  Year 1995 Publication Abbreviated Journal  
  Volume Issue Pages 743-746  
  Keywords P3 Proceeding; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher World Scientific Place of Publication Singapore Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #  
  Call Number UA @ lucian @ c:irua:12203 Serial 2974  
Permanent link to this record
 

 
Author (up) Xue, C.; He, A.; Milošević, M.V.; Silhanek, A., V; Zhou, Y.-H. url  doi
openurl 
  Title Open circuit voltage generated by dragging superconducting vortices with a dynamic pinning potential Type A1 Journal article
  Year 2019 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 21 Issue 11 Pages 113044  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We theoretically investigate, through Ginzburg?Landau simulations, the possibility to induce an open circuit voltage in absence of applied current, by dragging superconducting vortices with a dynamic pinning array as for instance that created by a nearby sliding vortex lattice or moving laser spots. Different dynamic regimes, such as synchronous vortex motion or dynamic vortex chains consisting of laggard vortices, can be observed by varying the velocity of the sliding pinning potential and the applied magnetic field. Additionally, due to the edge barrier, significantly different induced voltage is found depending on whether the vortices are dragged along the superconducting strip or perpendicular to the lateral edges. The output voltage in the proposed mesoscopic superconducting dynamo can be tuned by varying size, density and directions of the sliding pinning potential.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000498853700001 Publication Date 2019-11-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 6 Open Access  
  Notes Approved Most recent IF: 3.786  
  Call Number UA @ admin @ c:irua:165158 Serial 6317  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M. url  doi
openurl 
  Title Monolayer fluoro-InSe : formation of a thin monolayer via fluorination of InSe Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 100 Issue 2 Pages 024108  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By performing density functional theory-based first-principles calculations, the formation of a thin monolayer structure, namely InSeF, via fluorination of monolayer InSe is predicted. It is shown that strong interaction of F and In atoms leads to the detachment of In-Se layers in monolayer InSe and 1T-like monolayer InSeF structure is formed. Monolayer InSeF is found to be dynamically stable in terms of its phonon band dispersions. In addition, its Raman spectrum is shown to exhibit totally distinctive features as compared to monolayer InSe. The electronic band dispersions reveal that monolayer InSeF is a direct gap semiconductor whose valence and conduction band edges reside at the Gamma point. Moreover, the orientation-dependent linear elastic properties of monolayer InSeF are investigated in terms of the in-plane stiffness and Poisson ratio. It is found that monolayer InSeF displays strong in-plane anisotropy in elastic constants and it is slightly softer material as compared to monolayer InSe. Overall, it is proposed that a thin, direct gap semiconducting monolayer InSeF can be formed by full fluorination of monolayer InSe as a new member of the two-dimensional family.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000477885700003 Publication Date 2019-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 9 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:161891 Serial 5423  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M. url  doi
openurl 
  Title Stable anisotropic single-layer of ReTe₂ : a first principles prediction Type A1 Journal article
  Year 2020 Publication Turkish Journal of Physics Abbreviated Journal  
  Volume 44 Issue 5 Pages 450-457  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In order to investigate the structural, vibrational, electronic, and mechanical features of single-layer ReTe2 first-principles calculations are performed. Dynamical stability analyses reveal that single-layer ReTe2 crystallize in a distorted phase while its 1H and 1T phases are dynamically unstable. Raman spectrum calculations show that single-layer distorted phase of ReTe2 exhibits 18 Raman peaks similar to those of ReS2 and ReSe2. Electronically, single-layer ReTe2 is shown to be an indirect gap semiconductor with a suitable band gap for optoelectronic applications. In addition, it is found that the formation of Re-units in the crystal induces anisotropic mechanical parameters. The in-plane stiffness and Poisson ratio are shown to be significantly dependent on the lattice orientation. Our findings indicate that single-layer form of ReTe2 can only crystallize in a dynamically stable distorted phase formed by the Re-units. Single-layer of distorted ReTe2 can be a potential in-plane anisotropic material for various nanotechnology applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000585330600004 Publication Date 2020-09-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1300-0101 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes ; Computational resources were provided by the Scientific and Technological Research Council of Turkey (TUBITAK) Turkish Academic Network and Information Center (ULAKBIM), High Performance and Grid Computing Center (TR-Grid e-Infrastructure) and by Flemish Supercomputer Center (VSC). This work was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:174296 Serial 6698  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Bacaksiz, C.; Unsal, E.; Akbali, B.; Senger, R.T.; Sahin, H. url  doi
openurl 
  Title Strain mapping in single-layer two-dimensional crystals via Raman activity Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 97 Issue 11 Pages 115427  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By performing density functional theory-based ab initio calculations, Raman-active phonon modes of single-layer two-dimensional (2D) materials and the effect of in-plane biaxial strain on the peak frequencies and corresponding activities of the Raman-active modes are calculated. Our findings confirm the Raman spectrum of the unstrained 2D crystals and provide expected variations in the Raman-active modes of the crystals under in-plane biaxial strain. The results are summarized as follows: (i) frequencies of the phonon modes soften (harden) under applied tensile (compressive) strains; (ii) the response of the Raman activities to applied strain for the in-plane and out-of-plane vibrational modes have opposite trends, thus, the built-in strains in the materials can be monitored by tracking the relative activities of those modes; (iii) in particular, the A peak in single-layer Si and Ge disappears under a critical tensile strain; (iv) especially in mono-and diatomic single layers, the shift of the peak frequencies is a stronger indication of the strain rather than the change in Raman activities; (v) Raman-active modes of single-layer ReX2 (X = S, Se) are almost irresponsive to the applied strain. Strain-induced modifications in the Raman spectrum of 2D materials in terms of the peak positions and the relative Raman activities of the modes could be a convenient tool for characterization.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000427799300006 Publication Date 2018-03-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 21 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 116C073. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:150840UA @ admin @ c:irua:150840 Serial 4979  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Horzum, S.; Torun, E.; Peeters, F.M.; Senger, R.T. url  doi
openurl 
  Title Nitrogenated, phosphorated and arsenicated monolayer holey graphenes Type A1 Journal article
  Year 2016 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 18 Issue 18 Pages 3144-3150  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Motivated by a recent experiment that reported the synthesis of a new 2D material nitrogenated holey graphene (C2N) [Mahmood et al., Nat. Commun., 2015, 6, 6486], the electronic, magnetic, and mechanical properties of nitrogenated (C2N), phosphorated (C2P) and arsenicated (C2As) monolayer holey graphene structures are investigated using first-principles calculations. Our total energy calculations indicate that, similar to the C2N monolayer, the formation of the other two holey structures are also energetically feasible. Calculated cohesive energies for each monolayer show a decreasing trend going from the C2N to C2As structure. Remarkably, all the holey monolayers considered are direct band gap semiconductors. Regarding the mechanical properties (in-plane stiffness and Poisson ratio), we find that C2N has the highest in-plane stiffness and the largest Poisson ratio among the three monolayers. In addition, our calculations reveal that for the C2N, C2P and C2As monolayers, creation of N and P defects changes the semiconducting behavior to a metallic ground state while the inclusion of double H impurities in all holey structures results in magnetic ground states. As an alternative to the experimentally synthesized C2N, C2P and C2As are mechanically stable and flexible semiconductors which are important for potential applications in optoelectronics.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000369506000095 Publication Date 2015-12-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 36 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; Approved Most recent IF: 4.123  
  Call Number UA @ lucian @ c:irua:132313 Serial 4214  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Mogulkoc, Y.; Akgenc, B.; Mogulkoc, A.; Peeters, F.M. doi  openurl
  Title Prediction of monoclinic single-layer Janus Ga₂ Te X (X = S and Se) : strong in-plane anisotropy Type A1 Journal article
  Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 104 Issue 4 Pages 045425  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By using density functional theory (DFT) based first-principles calculations, electronic, vibrational, piezo-electric, and optical properties of monoclinic Janus single-layer Ga2TeX (X = S or Se) are investigated. The dynamical, mechanical, and thermal stability of the proposed Janus single layers are verified by means of phonon bands, stiffness tensor, and quantum molecular dynamics simulations. The calculated vibrational spectrum reveals the either pure or coupled optical phonon branches arising from Ga-Te and Ga-X atoms. In addition to the in-plane anisotropy, single-layer Janus Ga2TeX exhibits additional out-of-plane asymmetry, which leads to important consequences for its electronic and optical properties. Electronic band dispersions indicate the direct band-gap semiconducting nature of the constructed Janus structures with energy band gaps falling into visible spectrum. Moreover, while orientation-dependent linear-elastic properties of Janus single layers indicate their strong anisotropy, the calculated in-plane stiffness values reveal the ultrasoft nature of the structures. In addition, predicted piezoelectric coefficients show that while there is a strong in-plane anisotropy between piezoelectric constants along armchair (AC) and zigzag (ZZ) directions, there exists a tiny polarization along the out-of-plane direction as a result of the formation of Janus structure. The optical response to electromagnetic radiation has been also analyzed through density functional theory by considering the independent-particle approximation. Finally, the optical spectra of Janus Ga2TeX structures is investigated and it showed a shift from the ultraviolet region to the visible region. The fact that the spectrum is between these regions will allow it to be used in solar energy and many nanoelectronics applications. The predicted monoclinic single-layer Janus Ga2TeX are relevant for promising applications in optoelectronics, optical dichroism, and anisotropic nanoelasticity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000678811100007 Publication Date 2021-07-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 3 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:180404 Serial 7013  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Ozen, S.; Iyikanat, F.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Raman fingerprint of stacking order in HfS2-Ca(OH)(2) heterobilayer Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 99 Issue 20 Pages 205405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using density functional theory-based first-principles calculations, we investigate the stacking order dependence of the electronic and vibrational properties of HfS2-Ca(OH)(2) heterobilayer structures. It is shown that while the different stacking types exhibit similar electronic and optical properties, they are distinguishable from each other in terms of their vibrational properties. Our findings on the vibrational properties are the following: (i) from the interlayer shear (SM) and layer breathing (LBM) modes we are able to deduce the AB' stacking order, (ii) in addition, the AB' stacking type can also be identified via the phonon softening of E-g(I) and A(g)(III) modes which harden in the other two stacking types, and (iii) importantly, the ultrahigh frequency regime possesses distinctive properties from which we can distinguish between all stacking types. Moreover, the differences in optical and vibrational properties of various stacking types are driven by two physical effects, induced biaxial strain on the layers and the layer-layer interaction. Our results reveal that with both the phonon frequencies and corresponding activities, the Raman spectrum possesses distinctive properties for monitoring the stacking type in novel vertical heterostructures constructed by alkaline-earth-metal hydroxides.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000467387800010 Publication Date 2019-05-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 23 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under the Project No. 117F095. H.S. acknowledges support from Turkish Academy of Sciences under the GEBIP program. This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:160334 Serial 5226  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Peeters, F.M. url  doi
openurl 
  Title Stable single layer of Janus MoSO: strong out-of-plane piezoelectricity Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 101 Issue 15 Pages 155205-155208  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using density functional theory based first-principles calculations, we predict the dynamically stable 1H phase of a Janus single layer composed of S-Mo-O atomic layers. It is an indirect band gap semiconductor exhibiting strong polarization arising from the charge difference on the two surfaces. In contrast to 1H phases of MoS2 and MoO2, Janus MoSO is found to possess four Raman active phonon modes and a large out-of-plane piezoelectric coefficient which is absent in fully symmetric single layers of MoS2 and MoO2. We investigated the electronic and phononic properties under applied biaxial strain and found an electronic phase transition with tensile strain while the conduction band edge displays a shift when under compressive strain. Furthermore, single-layer MoSO exhibits phononic stability up to 5% of compressive and 11% of tensile strain with significant phonon shifts. The phonon instability is shown to arise from the soft in-plane and out-of-plane acoustic modes at finite wave vector. The large strain tolerance of Janus MoSO is important for nanoelastic applications. In view of the dynamical stability even under moderate strain, we expect that Janus MoSO can be fabricated in the common 1H phase with a strong out-of-plane piezoelectric coefficient.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000528507900003 Publication Date 2020-04-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.7 Times cited 49 Open Access  
  Notes ; Computational resources were provided by the Flemish Supercomputer Center (VSC). M.Y. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:169566 Serial 6614  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Electronic and vibrational properties of PbI2: From bulk to monolayer Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 8 Pages 085431  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we study the dependence of the electronic and vibrational properties of multilayered PbI2 crystals on the number of layers and focus on the electronic-band structure and the Raman spectrum. Electronic-band structure calculations reveal that the direct or indirect semiconducting behavior of PbI2 is strongly influenced by the number of layers. We find that at 3L thickness there is a direct-to-indirect band gap transition (from bulk-to-monolayer). It is shown that in the Raman spectrum two prominent peaks, A(1g) and E-g, exhibit phonon hardening with an increasing number of layers due to the interlayer van der Waals interaction. Moreover, the Raman activity of the A(1g) mode significantly increases with an increasing number of layers due to the enhanced out-of-plane dielectric constant in the few-layer case. We further characterize rigid-layer vibrations of low-frequency interlayer shear (C) and breathing (LB) modes in few-layer PbI2. A reduced monatomic (linear) chain model (LCM) provides a fairly accurate picture of the number of layers dependence of the low-frequency modes and it is shown also to be a powerful tool to study the interlayer coupling strength in layered PbI2.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000442667200008 Publication Date 2018-08-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 41 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. Part of this work was supported by FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153716UA @ admin @ c:irua:153716 Serial 5097  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Peeters, F.M.; Senger, R.T.; Sahin, H. url  doi
openurl 
  Title Nanoribbons: From fundamentals to state-of-the-art applications Type A1 Journal article
  Year 2016 Publication Applied physics reviews Abbreviated Journal Appl Phys Rev  
  Volume 3 Issue 3 Pages 041302  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Atomically thin nanoribbons (NRs) have been at the forefront of materials science and nanoelectronics in recent years. State-of-the-art research on nanoscale materials has revealed that electronic, magnetic, phononic, and optical properties may differ dramatically when their one-dimensional forms are synthesized. The present article aims to review the recent advances in synthesis techniques and theoretical studies on NRs. The structure of the review is organized as follows: After a brief introduction to low dimensional materials, we review different experimental techniques for the synthesis of graphene nanoribbons (GNRs) with their advantages and disadvantages. In addition, theoretical investigations on width and edge-shape-dependent electronic and magnetic properties, functionalization effects, and quantum transport properties of GNRs are reviewed. We then devote time to the NRs of the transition metal dichalcogenides (TMDs) family. First, various synthesis techniques, E-field-tunable electronic and magnetic properties, and edge-dependent thermoelectric performance of NRs of MoS2 and WS2 are discussed. Then, strongly anisotropic properties, growth-dependent morphology, and the weakly width-dependent bandgap of ReS2 NRs are summarized. Next we discuss TMDs having a T-phase morphology such as TiSe2 and stable single layer NRs of mono-chalcogenides. Strong edge-type dependence on characteristics of GaS NRs, width-dependent Seebeck coefficient of SnSe NRs, and experimental analysis on the stability of ZnSe NRs are reviewed. We then focus on the most recently emerging NRs belonging to the class of transition metal trichalcogenides which provide ultra-high electron mobility and highly anisotropic quasi-1D properties. In addition, width-, edge-shape-, and functionalization-dependent electronic and mechanical properties of blackphosphorus, a monoatomic anisotropic material, and studies on NRs of group IV elements (silicene, germanene, and stanene) are reviewed. Observation of substrate-independent quantum well states, edge and width dependent properties, the topological phase of silicene NRs are reviewed. In addition, H-2 concentration-dependent transport properties and anisotropic dielectric function of GeNRs and electric field and strain sensitive I-V characteristics of SnNRs are reviewed. We review both experimental and theoretical studies on the NRs of group III-V compounds. While defect and N-termination dependent conductance are highlighted for boron nitride NRs, aluminum nitride NRs are of importance due to their dangling bond, electric field, and strain dependent electronic and magnetic properties. Finally, superlattice structure of NRs of GaN/AlN, Si/Ge, G/BN, and MoS2/WS2 is reviewed. Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Amer inst physics Place of Publication Melville Editor  
  Language Wos 000390443800013 Publication Date 2016-11-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1931-9401 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.667 Times cited 63 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges the support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through Project No. 114F397. F.M.P. was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; Approved Most recent IF: 13.667  
  Call Number UA @ lucian @ c:irua:140299 Serial 4457  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Qin, Y.; Ozen, S.; Sayyad, M.; Peeters, F.M.; Tongay, S.; Sahin, H. pdf  doi
openurl 
  Title Quantum properties and applications of 2D Janus crystals and their superlattices Type A1 Journal article
  Year 2020 Publication Applied Physics Reviews Abbreviated Journal Appl Phys Rev  
  Volume 7 Issue 1 Pages 011311-11316  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional (2D) Janus materials are a new class of materials with unique physical, chemical, and quantum properties. The name “Janus” originates from the ancient Roman god which has two faces, one looking to the future while the other facing the past. Janus has been used to describe special types of materials which have two faces at the nanoscale. This unique atomic arrangement has been shown to present rather exotic properties with applications in biology, chemistry, energy conversion, and quantum sciences. This review article aims to offer a comprehensive review of the emergent quantum properties of Janus materials. The review starts by introducing 0D Janus nanoparticles and 1D Janus nanotubes, and highlights their difference from classical ones. The design principles, synthesis, and the properties of graphene-based and chalcogenide-based Janus layers are then discussed. A particular emphasis is given to colossal built-in potential in 2D Janus layers and resulting quantum phenomena such as Rashba splitting, skyrmionics, excitonics, and 2D magnetic ordering. More recent theoretical predictions are discussed in 2D Janus superlattices when Janus layers are stacked onto each other. Finally, we discuss the tunable quantum properties and newly predicted 2D Janus layers waiting to be experimentally realized. The review serves as a complete summary of the 2D Janus library and predicted quantum properties in 2D Janus layers and their superlattices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000519611500001 Publication Date 2020-02-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1931-9401 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 15 Times cited 107 Open Access  
  Notes ; S.T. acknowledges support from NSF Contract Nos. DMR 1552220, DMR 1904716, and NSF CMMI 1933214. H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. H.S. acknowledges support from the Turkish Academy of Sciences under the GEBIP program. M.Y. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. Part of this work was supported by the FLAG-ERA project TRANS2D-TMD. ; Approved Most recent IF: 15; 2020 IF: 13.667  
  Call Number UA @ admin @ c:irua:167712 Serial 6591  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T. doi  openurl
  Title Pentagonal monolayer crystals of carbon, boron nitride, and silver azide Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 118 Issue 118 Pages 104303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000361636900028 Publication Date 2015-09-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 79 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge the support from TUBITAK through Project No. 114F397. ; Approved Most recent IF: 2.068; 2015 IF: 2.183  
  Call Number UA @ lucian @ c:irua:128415 Serial 4223  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Senger, R.T.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Mechanical properties of monolayer GaS and GaSe crystals Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 94 Issue 94 Pages 245407  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The mechanical properties of monolayer GaS and GaSe crystals are investigated in terms of their elastic constants: in-plane stiffness (C), Poisson ratio (nu), and ultimate strength (sigma(U)) by means of first-principles calculations. The calculated elastic constants are compared with those of graphene and monolayer MoS2. Our results indicate that monolayer GaS is a stiffer material than monolayer GaSe crystals due to the more ionic character of the Ga-S bonds than the Ga-Se bonds. Although their Poisson ratio values are very close to each other, 0.26 and 0.25 for GaS and GaSe, respectively, monolayer GaS is a stronger material than monolayer GaSe due to its slightly higher sU value. However, GaS and GaSe crystals are found to be more ductile and flexible materials than graphene and MoS2. We have also analyzed the band-gap response of GaS and GaSe monolayers to biaxial tensile strain and predicted a semiconductor-metal crossover after 17% and 14% applied strain, respectively, for monolayer GaS and GaSe. In addition, we investigated how the mechanical properties are affected by charging. We found that the flexibility of single layer GaS and GaSe displays a sharp increase under 0.1e/cell charging due to the repulsive interactions between extra charges located on chalcogen atoms. These charging-controllable mechanical properties of single layers of GaS and GaSe can be of potential use for electromechanical applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000389503400008 Publication Date 2016-12-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9950;2469-9969; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 108 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through project 114F397. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:139229 Serial 4356  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Sevik, C.; Peeters, F.M. url  doi
openurl 
  Title Electronic, vibrational, elastic, and piezoelectric properties of monolayer Janus MoSTe phases: A first-principles study Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 100 Issue 4 Pages 045415  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By performing density functional theory based first-principles calculations, the electronic, vibrational, elastic, and piezoelectric properties of two dynamically stable crystal phases of monolayer Janus MoSTe, namely 1H-MoSTe and 1T'-MoSTe, are investigated. Vibrational frequency analysis reveals that the other possible crystal structure, 1T-MoSTe, of this Janus monolayer does not exhibit dynamical stability. The 1H-MoSTe phase is found to be an indirect band-gap semiconductor while 1T'-MoSTe is predicted as small-gap semiconductor. Notably, in contrast to the direct band-gap nature of monolayers 1H-MoS2 and 1H-MoTe2, 1H-MoSTe is found to be an indirect gap semiconductor driven by the induced surface strains on each side of the structure. The calculated Raman spectrum of each structure shows unique character enabling us to clearly distinguish the stable crystal phases via Raman measurements. The systematic piezoelectric stress and strain coefficient analysis reveals that out-of-plane piezoelectricity appears in 1H-MoSTe and the noncentral symmetric 1T'-MoSTe has large piezoelectric coefficients. Static total-energy calculations show clearly that the formation of 1T'-MoSTe is feasible by using 1T'-MoTe2 as a basis monolayer. Therefore, we propose that the Janus MoSTe structure can be fabricated in two dynamically stable phases which possess unique electronic, dynamical, and piezoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000476687800003 Publication Date 2019-07-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 91 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). This work was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:161899 Serial 5411  
Permanent link to this record
 

 
Author (up) Yagmurcukardes, M.; Sozen, Y.; Baskurt, M.; Peeters, F.M.; Sahin, H. doi  openurl
  Title Interface-dependent phononic and optical properties of GeO/MoSO heterostructures Type A1 Journal article
  Year 2021 Publication Nanoscale Abbreviated Journal Nanoscale  
  Volume Issue Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The interface-dependent electronic, vibrational, piezoelectric, and optical properties of van der Waals heterobilayers, formed by buckled GeO (b-GeO) and Janus MoSO structures, are investigated by means of first-principles calculations. The electronic band dispersions show that O/Ge and S/O interface formations result in a type-II band alignment with direct and indirect band gaps, respectively. In contrast, O/O and S/Ge interfaces give rise to the formation of a type-I band alignment with an indirect band gap. By considering the Bethe-Salpeter equation (BSE) on top of G(0)W(0) approximation, it is shown that different interfaces can be distinguished from each other by means of the optical absorption spectra as a consequence of the band alignments. Additionally, the low- and high-frequency regimes of the Raman spectra are also different for each interface type. The alignment of the individual dipoles, which is interface-dependent, either weakens or strengthens the net dipole of the heterobilayers and results in tunable piezoelectric coefficients. The results indicate that the possible heterobilayers of b-GeO/MoSO asymmetric structures possess various electronic, optical, and piezoelectric properties arising from the different interface formations and can be distinguished by means of various spectroscopic techniques.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000738899600001 Publication Date 2021-12-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 7.367 Times cited 2 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 7.367  
  Call Number UA @ admin @ c:irua:184722 Serial 6998  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: