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Author Yagmurcukardes, M.; Senger, R.T.; Peeters, F.M.; Sahin, H.
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 (down)
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
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Author Khoeini, F.; Shakouri; Peeters, F.M.
Title Peculiar half-metallic state in zigzag nanoribbons of MoS2 : spin filtering Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 94 Pages 125412
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Layered structures of molybdenum disulfide (MoS2) belong to a new class of two-dimensional (2D) semiconductor materials in which monolayers exhibit a direct band gap in their electronic spectrum. This band gap has recently been shown to vanish due to the presence of metallic edge modes when MoS2 monolayers are terminated by zigzag edges on both sides. Here, we demonstrate that a zigzag nanoribbon of MoS2, when exposed to an external exchange field in combination with a transverse electric field, has the potential to exhibit a peculiar half-metallic nature and thereby allows electrons of only one spin direction to move. The peculiarity of such spin-selective conductors originates from a spin switch near the gap-closing region, so the allowed spin orientation can be controlled by means of an external gate voltage. It is shown that the induced half-metallic phase is resistant to random fluctuations of the exchange field as well as the presence of edge vacancies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000383238800009 Publication Date 2016-09-09
Series Editor Series Title Abbreviated Series Title (down)
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 38 Open Access
Notes ; ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:137130 Serial 4360
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Author Van der Donck, M.; De Beule, C.; Partoens, B.; Peeters, F.M.; Van Duppen, B.
Title Piezoelectricity in asymmetrically strained bilayer graphene Type A1 Journal article
Year 2016 Publication 2D materials Abbreviated Journal 2D Mater
Volume 3 Issue 3 Pages 035015
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the electronic properties of commensurate faulted bilayer graphene by diagonalizing the one-particle Hamiltonian of the bilayer system in a complete basis of Bloch states of the individual graphene layers. Our novel approach is very general and can be easily extended to any commensurate graphene-based heterostructure. Here, we consider three cases: (i) twisted bilayer graphene, (ii) bilayer graphene where triaxial stress is applied to one layer and (iii) bilayer graphene where uniaxial stress is applied to one layer. We show that the resulting superstructures can be divided into distinct classes, depending on the twist angle or the magnitude of the induced strain. The different classes are distinguished from each other by the interlayer coupling mechanism, resulting in fundamentally different low-energy physics. For the cases of triaxial and uniaxial stress, the individual graphene layers tend to decouple and we find significant charge transfer between the layers. In addition, this piezoelectric effect can be tuned by applying a perpendicular electric field. Finally, we show how our approach can be generalized to multilayer systems.
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Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000384072500003 Publication Date 2016-08-31
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.937 Times cited 10 Open Access
Notes ; This work was supported by the Research Foundation-Flanders (FWO-Vl) through aspirant research grants to MVDD, CDB, and BVD. ; Approved Most recent IF: 6.937
Call Number UA @ lucian @ c:irua:137203 Serial 4361
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Author Tomak, A.; Bacaksiz, C.; Mendirek, G.; Sahin, H.; Hur, D.; Gorgun, K.; Senger, R.T.; Birer, O.; Peeters, F.M.; Zareie, H.M.
Title Structural changes in a Schiff base molecular assembly initiated by scanning tunneling microscopy tip Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 27 Issue 27 Pages 335601
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We report the controlled self-organization and switching of newly designed Schiff base (E)-4-((4-(phenylethynyl) benzylidene) amino) benzenethiol (EPBB) molecules on a Au (111) surface at room temperature. Scanning tunneling microscopy and spectroscopy (STM/STS) were used to image and analyze the conformational changes of the EPBB molecules. The conformational change of the molecules was induced by using the STM tip while increasing the tunneling current. The switching of a domain or island of molecules was shown to be induced by the STM tip during scanning. Unambiguous fingerprints of the switching mechanism were observed via STM/STS measurements. Surface-enhanced Raman scattering was employed, to control and identify quantitatively the switching mechanism of molecules in a monolayer. Density functional theory calculations were also performed in order to understand the microscopic details of the switching mechanism. These calculations revealed that the molecular switching behavior stemmed from the strong interaction of the EPBB molecules with the STM tip. Our approach to controlling intermolecular mechanics provides a path towards the bottom-up assembly of more sophisticated molecular machines.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000383780500012 Publication Date 2016-07-05
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 2 Open Access
Notes ; The authors acknowledge financial support from TUBITAK (PROJECT NO: 112T507). This work was also supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid-Infrastructure). HS is supported by an FWO Pegasus Long Marie Curie Fellowship. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:137155 Serial 4363
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Author Yagmurcukardes, M.; Torun, E.; Senger, R.T.; Peeters, F.M.; Sahin, H.
Title Mg(OH)2-WS2 van der Waals heterobilayer : electric field tunable band-gap crossover Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 94 Pages 195403
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Magnesium hydroxide [Mg(OH)(2)] has a layered brucitelike structure in its bulk form and was recently isolated as a new member of two-dimensional monolayer materials. We investigated the electronic and optical properties of monolayer crystals of Mg(OH)(2) and WS2 and their possible heterobilayer structure by means of first-principles calculations. It was found that both monolayers of Mg(OH)(2) and WS2 are direct-gap semiconductors and these two monolayers form a typical van der Waals heterostructure with a weak interlayer interaction and a type-II band alignment with a staggered gap that spatially separates electrons and holes. We also showed that an out-of-plane electric field induces a transition from a staggered to a straddling-type heterojunction. Moreover, by solving the Bethe-Salpeter equation on top of single-shot G(0)W(0) calculations, we show that the low-energy spectrum of the heterobilayer is dominated by the intralyer excitons of the WS2 monolayer. Because of the staggered interfacial gap and the field-tunable energy-band structure, the Mg(OH)(2)-WS2 heterobilayer can become an important candidate for various optoelectronic device applications in nanoscale.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000386769400007 Publication Date 2016-11-03
Series Editor Series Title Abbreviated Series Title (down)
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 38 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. is supported by a FWOPegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge support from TUBITAK through Project No. 114F397. H.S. acknowledges support from Bilim Akademisi – The Science Academy, Turkey, under the BAGEP program. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:138205 Serial 4364
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Author Yagmurcukardes, M.; Peeters, F.M.; Senger, R.T.; Sahin, H.
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 (down)
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
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Author Iyikanat, F.; Senger, R.T.; Peeters, F.M.; Sahin, H.
Title Quantum-Transport Characteristics of a p-n Junction on Single-Layer TiS3 Type A1 Journal article
Year 2016 Publication ChemPhysChem : a European journal of chemical physics and physical chemistry Abbreviated Journal Chemphyschem
Volume 17 Issue 17 Pages 3985-3991
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By using density functional theory and non-equilibrium Green's function-based methods, we investigated the electronic and transport properties of a TiS3 monolayer p-n junction. We constructed a lateral p-n junction on a TiS3 monolayer using Li and F adatoms. An applied bias voltage caused significant variability in the electronic and transport properties of the TiS3 p-n junction. In addition, the spin-dependent current-volt-age characteristics of the constructed TiS3 p-n junction were analyzed. Important device characteristics were found, such as negative differential resistance and rectifying diode behaviors for spin-polarized currents in the TiS3 p-n junction. These prominent conduction properties of the TiS3 p-n junction offer remarkable opportunities for the design of nanoelectronic devices based on a recently synthesized single-layered material.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000389534800018 Publication Date 2016-09-29
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1439-4235 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.075 Times cited 12 Open Access
Notes ; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and the Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). FI, HS, and RTS acknowledge the support from TUBITAK Project No 114F397. H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. ; Approved Most recent IF: 3.075
Call Number UA @ lucian @ c:irua:140245 Serial 4458
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Author Petrovic, M.D.; Peeters, F.M.
Title Quantum transport in graphene Hall bars: Effects of vacancy disorder Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 94 Pages 235413
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the tight-binding model, we investigate the influence of vacancy disorder on electrical transport in graphene Hall bars in the presence of quantizing magnetic fields. Disorder, induced by a random distribution of monovacancies, breaks the graphene sublattice symmetry and creates states localized on the vacancies. These states are observable in the bend resistance, as well as in the total DOS. Their energy is proportional to the square root of the magnetic field, while their localization length is proportional to the cyclotron radius. At the energies of these localized states, the electron current flows around the monovacancies and, as we show, it can follow unexpected paths depending on the particular arrangement of vacancies. We study how these localized states change with the vacancy concentration, and what are the effects of including the next-nearest-neighbor hopping term. Our results are also compared with the situation when double vacancies are present in the system. Double vacancies also induce localized states, but their energy and magnetic field dependencies are different. Their localization energy scales linearly with the magnetic field, and their localization length appears not to depend on the field strength.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000389574200005 Publication Date 2016-12-14
Series Editor Series Title Abbreviated Series Title (down)
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 14 Open Access
Notes ; This work was supported by the Methusalem program of the Flemish government. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:140237 Serial 4459
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Author Michel, K.H.; Neek-Amal, M.; Peeters, F.M.
Title Static flexural modes and piezoelectricity in 2D and layered crystals Type A1 Journal article
Year 2016 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B
Volume 253 Issue 253 Pages 2311-2315
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Piezo- and flexoelectricity are manifestations of electromechanical coupling in solids with potential applications in nanoscale materials. Naumov etal. [Phys. Rev. Lett. 102, 217601 (2009)] have shown by first principles calculations that a monolayer BN sheet becomes macroscopically polarized in-plane when in a corrugated state. Here, we investigate the interplay of layer corrugation and in-plane polarization by atomistic lattice dynamics. We treat the coupling between static flexural modes and in-plane atomic ion displacements as an anharmonic effect, similar to the membrane effect that is at the origin of negative thermal expansion in layered crystals. We have derived analytical expressions for the corrugation-induced static in-plane strains and the optical displacements with the resulting polarization response functions. Beyond h-BN, the theory applies to transition metal dichalcogenides and dioxides. Numerical calculations show that the effects are considerably stronger for 2D h-BN than for 2H-MoS2.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000390339000002 Publication Date 2016-10-21
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0370-1972 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.674 Times cited 5 Open Access
Notes ; The authors acknowledge useful discussions with L. Wirtz, A. Molina-Sanchez, and C. Sevik. This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.674
Call Number UA @ lucian @ c:irua:140309 Serial 4462
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Author Milovanović, S.P.; Peeters, F.M.
Title Strain controlled valley filtering in multi-terminal graphene structures Type A1 Journal article
Year 2016 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 109 Issue 109 Pages 203108
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Valley-polarized currents can be generated by local straining of multi-terminal graphene devices. The pseudo-magnetic field created by the deformation allows electrons from only one valley to transmit, and a current of electrons from a single valley is generated at the opposite side of the locally strained region. We show that valley filtering is most effective with bumps of a certain height and width. Despite the fact that the highest contribution to the polarized current comes from electrons from the lowest sub-band, contributions of other sub-bands are not negligible and can significantly enhance the output current. Published by AIP Publishing.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000388000000049 Publication Date 2016-11-16
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 50 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN. ; Approved Most recent IF: 3.411
Call Number UA @ lucian @ c:irua:139165 Serial 4463
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Author Milovanovic, S.P.; Peeters, F.M.
Title Strained graphene Hall bar Type A1 Journal article
Year 2017 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 29 Issue 29 Pages 075601
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effects of strain, induced by a Gaussian bump, on the magnetic field dependent transport properties of a graphene Hall bar are investigated. The numerical simulations are performed using both classical and quantum mechanical transport theory and we found that both approaches exhibit similar characteristic features. The effects of the Gaussian bump are manifested by a decrease of the bend resistance, RB, around zero-magnetic field and the occurrence of side-peaks in RB. These features are explained as a consequence of bump-assisted scattering of electrons towards different terminals of the Hall bar. Using these features we are able to give an estimate of the size of the bump. Additional oscillations in RB are found in the quantum description that are due to the population/depopulation of Landau levels. The bump has a minor influence on the Hall resistance even for very high values of the pseudo-magnetic field. When the bump is placed outside the center of the Hall bar valley polarized electrons can be collected in the leads.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000391584900001 Publication Date 2016-12-24
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 12 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN. ; Approved Most recent IF: 2.649
Call Number UA @ lucian @ c:irua:140381 Serial 4464
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Author Krstajić, P.M.; Van Duppen, B.; Peeters, F.M.
Title Plasmons and their interaction with electrons in trilayer graphene Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 88 Issue 19 Pages 195423
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The interaction between electrons and plasmons in trilayer graphene is investigated within the Overhauser approach resulting in the “plasmaron” quasiparticle. This interaction is cast into a field theoretical problem, and its effect on the energy spectrum is calculated using improved Wigner-Brillouin perturbation theory. The plasmaron spectrum is shifted with respect to the bare electron spectrum by ΔE(k)∼150−200meV for ABC stacked trilayer graphene and for ABA trilayer graphene by ΔE(k)∼30−150 meV[ ΔE(k) ∼1 −5meV] for the hyperbolic (linear) part of the spectrum. The shift in general increases with the electron concentration and electron momentum. The dispersion of plasmarons is more pronounced in ABC stacked than in ABA stacked trilayer graphene, because of the different energy band structure and their different plasmon dispersion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000327239200003 Publication Date 2013-11-21
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 10 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), by the ESF-EuroGRAPHENE project CON-GRAN, and by the Serbian Ministry of Education and Science, within the Project No. TR 32008. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number CMT @ cmt @ c:irua:112702 Serial 4489
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Author Li, L.L.; Moldovan, D.; Vasilopoulos, P.; Peeters, F.M.
Title Aharonov-Bohm oscillations in phosphorene quantum rings Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 20 Pages 205426
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The Aharonov-Bohm (AB) effect in square phosphorene quantum rings, with armchair and zigzag edges, is investigated using the tight-binding method. The energy spectra and wave functions of such rings, obtained as a function of the magnetic flux Phi threading the ring, are strongly influenced by the ringwidthW, an in-plane electric field E-p, and a side-gating potential V-g. Compared to a square dot, the ring shows an enhanced confinement due to its inner edges and an interedge coupling along the zigzag direction, both of which strongly affect the energy spectrum and the wave functions. The energy spectrum that is gapped consists of a regular part, of conduction (valence) band states, that shows the usual AB oscillations in the higher-(lower-) energy region, and of edge states, in the gap, that exhibit no AB oscillations. As the width W decreases, the AB oscillations become more distinct and regular and their period is close to Phi(0)/2, where the flux quantum Phi(0) = h/e is the period of an ideal circular ring (W -> 0). Both the electric field E-p and the side-gating potential V-g reduce the amplitude of the AB oscillations. The amplitude can be effectively tuned by E-p or V-g and exhibits an anisotropic behavior for different field directions or side-gating configurations.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000402003700010 Publication Date 2017-05-23
Series Editor Series Title Abbreviated Series Title (down)
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 16 Open Access
Notes ; This work was financially supported by the Chinese Academy of Sciences, the Flemish Science Foundation (FWO-V1), and by the Canadian NSERC Grant No. OGP0121756 (P.V.). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:144267 Serial 4638
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Author Li, L.L.; Zarenia, M.; Xu, W.; Dong, H.M.; Peeters, F.M.
Title Exciton states in a circular graphene quantum dot: Magnetic field induced intravalley to intervalley transition Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 045409
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The magnetic-field dependence of the energy spectrum, wave function, binding energy, and oscillator strength of exciton states confined in a circular graphene quantum dot (CGQD) is obtained within the configuration interaction method. We predict that (i) excitonic effects are very significant in the CGQD as a consequence of a combination of geometric confinement, magnetic confinement, and reduced screening; (ii) two types of excitons (intravalley and intervalley) are present in the CGQD because of the valley degree of freedom in graphene; (iii) the intravalley and intervalley exciton states display different magnetic-field dependencies due to the different electron-hole symmetries of the single-particle energy spectra; (iv) with increasing magnetic field, the exciton ground state in the CGQD undergoes an intravalley to intervalley transition accompanied by a change of angular momentum; (v) the exciton binding energy does not increase monotonically with the magnetic field due to the competition between geometric and magnetic confinements; and (vi) the optical transitions of the intervalley and intravalley excitons can be tuned by the magnetic field, and valley-dependent excitonic transitions can be realized in a CGQD.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000391856000006 Publication Date 2017-01-12
Series Editor Series Title Abbreviated Series Title (down)
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 14 Open Access
Notes ; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grants No. 11304316, No. 11574319, and No. 11604380), and by the Chinese Academy of Sciences (CAS). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:141444 Serial 4555
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Author Berdiyorov, G.R.; Neek-Amal, M.; Hussein, I.A.; Madjet, M.E.; Peeters, F.M.
Title Large CO2 uptake on a monolayer of CaO Type A1 Journal article
Year 2017 Publication Journal of materials chemistry A : materials for energy and sustainability Abbreviated Journal J Mater Chem A
Volume 5 Issue 5 Pages 2110-2114
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Density functional theory calculations are used to study gas adsorption properties of a recently synthesized CaO monolayer, which is found to be thermodynamically stable in its buckled form. Due to its topology and strong interaction with the CO2 molecules, this material possesses a remarkably high CO2 uptake capacity (similar to 0.4 g CO2 per g adsorbent). The CaO + CO2 system shows excellent thermal stability (up to 1000 K). Moreover, the material is highly selective towards CO2 against other major greenhouse gases such as CH4 and N2O. These advantages make this material a very promising candidate for CO2 capture and storage applications.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000395074300035 Publication Date 2016-12-19
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.867 Times cited 2 Open Access
Notes ; ; Approved Most recent IF: 8.867
Call Number UA @ lucian @ c:irua:142034 Serial 4556
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Author Heshmati-Moulai, A.; Simchi, H.; Esmaeilzadeh, M.; Peeters, F.M.
Title Phase transition and spin-resolved transport in MoS2 nanoribbons Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 94 Pages 235424
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic structure and transport properties of monolayer MoS2 are studied using a tight-binding approach coupled with the nonequilibrium Green's function method. A zigzag nanoribbon of MoS2 is conducting due to the intersection of the edge states with the Fermi level that is located within the bulk gap. We show that applying a transverse electric field results in the disappearance of this intersection and turns the material into a semiconductor. By increasing the electric field the band gap undergoes a two stage linear increase after which it decreases and ultimately closes. It is shown that in the presence of a uniform exchange field, this electric field tuning of the gap can be exploited to open low energy domains where only one of the spin states contributes to the electronic conductance. This introduces possibilities in designing spin filters for spintronic applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000394546100005 Publication Date 2016-12-20
Series Editor Series Title Abbreviated Series Title (down)
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 7 Open Access
Notes ; ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:141978 Serial 4557
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Author Satarifard, V.; Mousaei, M.; Hadadi, F.; Dix, J.; Sobrino Fernández, M.; Carbone, P.; Beheshtian, J.; Peeters, F.M.; Neek-Amal, M.
Title Reversible structural transition in nanoconfined ice Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 064105
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The report on square ice sandwiched between two graphene layers by Algara-Siller et al. [Nature (London) 519, 443 (2015)] has generated a large interest in this system. By applying high lateral pressure on nanoconfined water, we found that monolayer ice is transformed to bilayer ice when the two graphene layers are separated by H = 6,7 angstrom. It was also found that three layers of a denser phase of ice with smaller lattice constant are formed if we start from bilayer ice and apply a lateral pressure of about 0.7 GPa with H = 8,9 angstrom. The lattice constant (2.5-2.6 angstrom) in both transitions is found to be smaller than those typical for the known phases of ice and water, i.e., 2.8 angstrom. We validate these results using ab initio calculations and find good agreement between ab initio O-O distance and those obtained from classical molecular dynamics simulations. The reversibility of the mentioned transitions is confirmed by decompressing the systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000393943300005 Publication Date 2017-02-16
Series Editor Series Title Abbreviated Series Title (down)
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 23 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:141994 Serial 4558
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Author Han, F.W.; Xu, W.; Li, L.L.; Zhang, C.; Dong, H.M.; Peeters, F.M.
Title Electronic and transport properties of n-type monolayer black phosphorus at low temperatures Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 115436
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a detailed theoretical study of the electronic and transport properties of monolayer black phosphorus (BP). This study is motivated by recent experimental activities in investigating n-type few-layer BP systems. The electron density of states, the screening length, and the low-temperature electron mobility are calculated for monolayer BP (MLBP). In particular, the electron transport mobilities along the armchair and zigzag directions are examined on the basis of the momentum-balance equation derived from a semiclassical Boltzmann equation. The anisotropic electron mobilities in MLBP along different directions are demonstrated where the electron-impurity scattering is considered. Furthermore, we compare the results obtained from two electronic band structures of MLBP and find that the simplified model can describe quite rightly the electronic and transport properties of MLBP. This study is relevant to the application of few-layer BP based electronic systems as advanced electronic devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000399140700012 Publication Date 2017-03-27
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 12 Open Access
Notes National Natural Science Foundation of China, 11574319 11304316 11304317 11604380 ; Ministry of Science and Technology of the People's Republic of China, 2011YQ130018 ; Chinese Academy of Sciences; Approved Most recent IF: 3.836
Call Number CMT @ cmt @ c:irua:142431 Serial 4564
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Author Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M.
Title Dependence of the shape of graphene nanobubbles on trapped substance Type A1 Journal article
Year 2017 Publication Nature communications Abbreviated Journal Nat Commun
Volume 8 Issue 8 Pages 15844
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000403417500001 Publication Date 2017-06-16
Series Editor Series Title Abbreviated Series Title (down)
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 44 Open Access
Notes We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). Approved Most recent IF: 12.124
Call Number CMT @ cmt @ c:irua:144189 Serial 4580
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Author Peelaers, H.; Durgun, E.; Partoens, B.; Bilc, D.I.; Ghosez, P.; Van de Walle, C.G.; Peeters, F.M.
Title Ab initio study of hydrogenic effective mass impurities in Si nanowires Type A1 Journal article
Year 2017 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 29 Issue 29 Pages 095303
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effect of B and P dopants on the band structure of Si nanowires is studied using electronic structure calculations based on density functional theory. At low concentrations a dispersionless band is formed, clearly distinguishable from the valence and conduction bands. Although this band is evidently induced by the dopant impurity, it turns out to have purely Si character. These results can be rigorously analyzed in the framework of effective mass theory. In the process we resolve some common misconceptions about the physics of hydrogenic shallow impurities, which can be more clearly elucidated in the case of nanowires than would be possible for bulk Si. We also show the importance of correctly describing the effect of dielectric confinement, which is not included in traditional electronic structure calculations, by comparing the obtained results with those of G(0)W(0) calculations.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000395103900002 Publication Date 2017-01-06
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 1 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the NSF MRSEC Program under award No. DMR11-21053, and the Army Research Office (W911NF-13-1-0380). DIB acknowledges financial support from the grant of the Romanian National Authority for Scientific Research, CNCS UEFISCDI, project No. PN-II-RU-TE-2011-3-0085. Ph G acknowledges a research professorship of the Francqui foundation and financial support of the ARC project AIMED and FNRS project HiT4FiT. This research used resources of the Ceci HPC Center funded by F R S-FNRS (Grant No. 2.5020.1) and of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231. ; Approved Most recent IF: 2.649
Call Number UA @ lucian @ c:irua:142447 Serial 4584
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Author Li, L.; Kong, X.; Leenaerts, O.; Chen, X.; Sanyal, B.; Peeters, F.M.
Title Carbon-rich carbon nitride monolayers with Dirac cones : Dumbbell C4N Type A1 Journal article
Year 2017 Publication Carbon Abbreviated Journal Carbon
Volume 118 Issue 118 Pages 285-290
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Two-dimensional (2D) carbon nitride materials play an important role in energy-harvesting, energy-storage and environmental applications. Recently, a new carbon nitride, 2D polyaniline (C3N) was proposed [PNAS 113 (2016) 7414-7419]. Based on the structure model of this C3N monolayer, we propose two new carbon nitride monolayers, named dumbbell (DB) C4N-I and C4N-II. Using first-principles calculations, we systematically study the structure, stability, and band structure of these two materials. In contrast to other carbon nitride monolayers, the orbital hybridization of the C/N atoms in the DB C4N monolayers is sp(3). Remarkably, the band structures of the two DB C4N monolayers have a Dirac cone at the K point and their Fermi velocities (2.6/2.4 x 10(5) m/s) are comparable to that of graphene. This makes them promising materials for applications in high-speed electronic devices. Using a tight-binding model, we explain the origin of the Dirac cone. (C) 2017 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000401120800033 Publication Date 2017-03-16
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited 36 Open Access
Notes Approved Most recent IF: 6.337
Call Number UA @ lucian @ c:irua:143726 Serial 4588
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Author Arsoski, V.; Tadic, M.; Peeters, F.M.
Title Electric field tuning of the optical excitonic Aharonov-Bohm effect in nanodots grown by droplet epitaxy Type A1 Journal article
Year 2013 Publication Physica scripta Abbreviated Journal Phys Scripta
Volume T157 Issue Pages 014002
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Neutral excitons in axially symmetric GaAs nanodots embedded in an (Al, Ga) As matrix, which are formed by the droplet epitaxy technique, are investigated theoretically. An electric field perpendicular to the nanodot base results in both a vertical and an in-plane exciton polarization, which is beneficial for the appearance of the excitonic Aharonov-Bohm effect. In the range of low magnetic fields (below 5 Tesla), we found that the bright and dark exciton states can cross twice. This results in oscillations of the photoluminescence intensity with magnetic field, which are a striking manifestation of the optical excitonic Aharonov-Bohm effect.
Address
Corporate Author Thesis
Publisher Place of Publication Stockholm Editor
Language Wos 000332504600003 Publication Date 2013-11-15
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0031-8949 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.28 Times cited Open Access
Notes ; This work was supported by the EU Network of Excellence: SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 1.28; 2013 IF: 1.296
Call Number UA @ lucian @ c:irua:128901 Serial 4594
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Author Li, L.; Leenaerts, O.; Kong, X.; Chen, X.; Zhao, M.; Peeters, F.M.
Title Gallium bismuth halide GaBi-X2 (X = I, Br, Cl) monolayers with distorted hexagonal framework: Novel room-temperature quantum spin Hall insulators Type A1 Journal article
Year 2017 Publication Nano Research Abbreviated Journal Nano Res
Volume 10 Issue 10 Pages 2168-2180
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Quantum spin Hall (QSH) insulators with a large topologically nontrivial bulk gap are crucial for future applications of the QSH effect. Among these, group III-V monolayers and their halides, which have a chair structure (regular hexagonal framework), have been widely studied. Using first-principles calculations, we formulate a new structure model for the functionalized group III-V monolayers, which consist of rectangular GaBi-X-2 (X = I, Br, Cl) monolayers with a distorted hexagonal framework (DHF). These structures have a far lower energy than the GaBi-X-2 monolayers with a chair structure. Remarkably, the DHF GaBi-X-2 monolayers are all QSH insulators, which exhibit sizeable nontrivial band gaps ranging from 0.17 to 0.39 eV. The band gaps can be widely tuned by applying different spin-orbit coupling strengths, resulting in a distorted Dirac cone.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000401320700029 Publication Date 2017-04-08
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1998-0124 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.354 Times cited 15 Open Access
Notes ; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI. ; Approved Most recent IF: 7.354
Call Number UA @ lucian @ c:irua:143739 Serial 4598
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Author Singh, S.K.; Costamagna, S.; Neek-Amal, M.; Peeters, F.M.
Title Melting of partially fluorinated graphene : from detachment of fluorine atoms to large defects and random coils Type A1 Journal article
Year 2014 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 118 Issue 8 Pages 4460-4464
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The melting of fluorographene is very unusual and depends strongly on the degree of fluorination. For temperatures below 1000 K, fully fluorinated graphene (FFG) is thermomechanically more stable than graphene but at T-m approximate to 2800 K FFG transits to random coils which is almost 2 times lower than the melting temperature of graphene, i.e., 5300 K. For fluorinated graphene up to 30% ripples causes detachment of individual F-atoms around 2000 K, while for 40%-60% fluorination large defects are formed beyond 1500 K and beyond 60% of fluorination F-atoms remain bonded to graphene until melting. The results agree with recent experiments on the dependence of the reversibility of the fluorination process on the percentage of fluorination.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000332188100069 Publication Date 2014-01-22
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 16 Open Access
Notes ; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-VI). Financial support from the Collaborative program MINCyT (Argentina)-FWO(Belgium) is also acknowledged. ; Approved Most recent IF: 4.536; 2014 IF: 4.772
Call Number UA @ lucian @ c:irua:128874 Serial 4600
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Author Michel, K.H.; Çakir, D.; Sevik, C.; Peeters, F.M.
Title Piezoelectricity in two-dimensional materials : comparative study between lattice dynamics and ab initio calculations Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 125415
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The elastic constant C-11 and piezoelectric stress constant e(1),(11) of two-dimensional (2D) dielectric materials comprising h-BN, 2H-MoS2, and other transition-metal dichalcogenides and dioxides are calculated using lattice dynamical theory. The results are compared with corresponding quantities obtained with ab initio calculations. We identify the difference between clamped-ion and relaxed-ion contributions with the dependence on inner strains which are due to the relative displacements of the ions in the unit cell. Lattice dynamics allows us to express the inner-strain contributions in terms of microscopic quantities such as effective ionic charges and optoacoustical couplings, which allows us to clarify differences in the piezoelectric behavior between h-BN and MoS2. Trends in the different microscopic quantities as functions of atomic composition are discussed.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000396013400005 Publication Date 2017-03-11
Series Editor Series Title Abbreviated Series Title (down)
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 29 Open Access
Notes ; The authors acknowledge useful discussions with L. Wirtz and A. Molina-Sanchez. This work was supported by the Methusalem program and the Fonds voor Wetenschappelijk Onderzoek-Vlaanderen. Computational resources were provided by HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:142444 Serial 4603
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Author Petrovic, M.D.; Peeters, F.M.
Title Quantum transport in graphene Hall bars : effects of side gates Type A1 Journal article
Year 2017 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 257 Issue 257 Pages 20-26
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Quantum electron transport in side-gated graphene Hall bars is investigated in the presence of quantizing external magnetic fields. The asymmetric potential of four side-gates distorts the otherwise flat bands of the relativistic Landau levels, and creates new propagating states in the Landau spectrum (i.e. snake states). The existence of these new states leads to an interesting modification of the bend and Hall resistances, with new quantizing plateaus appearing in close proximity of the Landau levels. The electron guiding in this system can be understood by studying the current density profiles of the incoming and outgoing modes. From the fact that guided electrons fully transmit without any backscattering (similarly to edge states), we are able to analytically predict the values of the quantized resistances, and they match the resistance data we obtain with our numerical (tight-binding) method. These insights in the electron guiding will be useful in predicting the resistances for other side-gate configurations, and possibly in other system geometries, as long as there is no backscattering of the guided states.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000401101400005 Publication Date 2017-04-02
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0038-1098 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.554 Times cited Open Access
Notes ; This work was supported by the Methusalem programme of the Flemish government. One of us (F. M. Peeters) acknowledges correspondence with K. Novoselov. ; Approved Most recent IF: 1.554
Call Number UA @ lucian @ c:irua:143761 Serial 4604
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Author Petrovic, M.D.; Milovanović, S.P.; Peeters, F.M.
Title Scanning gate microscopy of magnetic focusing in graphene devices : quantum versus classical simulation Type A1 Journal article
Year 2017 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 28 Issue 28 Pages 185202
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We compare classical versus quantum electron transport in recently investigated magnetic focusing devices (Bhandari et al 2016 Nano Lett. 16 1690) exposed to the perturbing potential of a scanning gate microscope (SGM). Using the Landauer-Buttiker formalism for a multi-terminal device, we calculate resistance maps that are obtained as the SGM tip is scanned over the sample. There are three unique regimes in which the scanning tip can operate (focusing, repelling, and mixed regime) which are investigated. Tip interacts mostly with electrons with cyclotron trajectories passing directly underneath it, leaving a trail of modified current density behind it. Other (indirect) trajectories become relevant when the tip is placed near the edges of the sample, and current is scattered between the tip and the edge. We point out that, in contrast to SGM experiments on gapped semiconductors, the STM tip can induce a pn junction in graphene, which improves contrast and resolution in SGM. We also discuss possible explanations for spatial asymmetry of experimentally measured resistance maps, and connect it with specific configurations of the measuring probes.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000399273800001 Publication Date 2017-03-17
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 7 Open Access
Notes ; This work was supported by the Methusalem program of the Flemish government. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:143639 Serial 4607
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Author de Sousa, G.O.; da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M.
Title Unusual quantum confined Stark effect and Aharonov-Bohm oscillations in semiconductor quantum rings with anisotropic effective masses Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 205414
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effects of external electric and magnetic fields on the energy spectrum of quantum rings made out of a bidimensional semiconductor material with anisotropic band structures are investigated within the effective-mass model. The interplay between the effective-mass anisotropy and the radial confinement leads to wave functions that are strongly localized at two diametrically opposite regions where the kinetic energy is lowest due to the highest effective mass. We show that this quantum phenomenon has clear consequences on the behavior of the energy states in the presence of applied in-plane electric fields and out-of-plane magnetic fields. In the former, the quantum confined Stark effect is observed with either linear or quadratic shifts, depending on the direction of the applied field. As for the latter, the usual Aharonov-Bohm oscillations are not observed for a circularly symmetric confining potential, however they can be reinstated if an elliptic ring with an appropriate aspect ratio is chosen.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000401230600007 Publication Date 2017-05-12
Series Editor Series Title Abbreviated Series Title (down)
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 19 Open Access
Notes ; This work was financially supported by CNPq under the PRONEX/FUNCAP grants, CAPES Foundation, the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:143746 Serial 4610
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Author Zarenia, M.; Neilson, D.; Partoens, B.; Peeters, F.M.
Title Wigner crystallization in transition metal dichalcogenides : a new approach to correlation energy Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 115438
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We introduce a new approach for the correlation energy of one- and two-valley two-dimensional electron gas (2DEG) systems. Our approach is based on an interpolation between two limits, a random phase approximation at high densities and a classical approach at low densities which gives excellent agreement with available Quantum Monte Carlo (QMC) calculations. The two-valley 2DEG model is introduced to describe the electron correlations in monolayer transition metal dichalcogenides (TMDs). We study the zero-temperature transition from a Fermi liquid to a quantum Wigner crystal phase in monolayer TMDs. Consistent with QMC, we find that electrons crystallize at r(s) = 31 in one-valley 2DEG. For two valleys, we predict Wigner crystallization at r(s) = 30, implying that valley degeneracy has little effect on the critical r(s), in contrast to an earlier claim.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000399141200003 Publication Date 2017-03-30
Series Editor Series Title Abbreviated Series Title (down)
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 18 Open Access
Notes ; This work was partially supported by the Flanders Research Foundation (FWO) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:142428 Serial 4613
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Author Cavalcante, L.S.; Chaves, A.; da Costa, D.R.; Farias, G.A.; Peeters, F.M.
Title All-strain based valley filter in graphene nanoribbons using snake states Type A1 Journal article
Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 7 Pages 075432
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A pseudomagnetic field kink can be realized along a graphene nanoribbon using strain engineering. Electron transport along this kink is governed by snake states that are characterized by a single propagation direction. Those pseudomagnetic fields point towards opposite directions in the K and K' valleys, leading to valley polarized snake states. In a graphene nanoribbon with armchair edges this effect results in a valley filter that is based only on strain engineering. We discuss how to maximize this valley filtering by adjusting the parameters that define the stress distribution along the graphene ribbon.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000381889300002 Publication Date 2016-08-23
Series Editor Series Title Abbreviated Series Title (down)
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 29 Open Access
Notes ; Discussions with R. Grassi are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq), under the PRONEX/FUNCAP and Science Without Borders (SWB) programs, CAPES, the Lemann Foundation, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:144667 Serial 4639
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