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| Author | Lin, N.S.; Misko, V.R.; Peeters, F.M. | ||||
| Title | Dynamics of multishell vortex structures in mesoscopic superconducting Corbino disks | Type | A1 Journal article | ||
| Year | 2010 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 81 | Issue | 13 | Pages | 134504,1-134504,11 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract  |
We study the dynamics of vortex shells in mesoscopic superconducting Corbino disks, where vortices form shells as recently observed in micrometer-sized Nb disks. Due to the interplay between the vortex-vortex interaction, the gradient Lorentz force and the (in)commensurability between the numbers of vortices in shells, the process of angular melting of vortex-shell configurations becomes complex. Angular melting can start either from the center of the disk (where the shear stress is maximum) or from its boundary (where the shear stress is minimum) depending on the specific vortex configuration. Furthermore, we found that two kinds of defects can exist in such vortex-shell structures: intrashell and intershell defects. An intrashell defect may lead to an inverse dynamic behavior, i.e., one of the vortex shells under a stronger driving force can rotate slower than the adjacent shell that is driven by a weaker Lorentz force. An intershell defect always locks more than two shells until the gradient of the Lorentz force becomes large enough to break the rigid-body rotation of the locked shells. Such a lock-unlock process leads to hysteresis in the angular velocities of the shells. | ||||
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| Language | Wos | 000277207900079 | Publication Date | 2010-04-02 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 11 | Open Access | |
| Notes | ; This work was supported by the “Odysseus” program of the Flemish Government and the Flemish Science Foundation (FWO-V1), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-V1. ; | Approved | Most recent IF: 3.836; 2010 IF: 3.774 | ||
| Call Number | UA @ lucian @ c:irua:82803 | Serial | 779 | ||
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| Author | Lin, N.S.; Heitmann, T.W.; Yu, K.; Plourde, B.L.T.; Misko, V.R. | ||||
| Title | Rectification of vortex motion in a circular ratchet channel | Type | A1 Journal article | ||
| Year | 2011 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 84 | Issue | 14 | Pages | 144511-144511,12 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the dynamics of vortices in an asymmetric (i.e., consisting of triangular cells) ring channel driven by an external ac current I in a Corbino setup. The asymmetric potential rectifies the motion of vortices and induces a net vortex flow without any unbiased external drive, i.e., the ratchet effect. We show that the net flow of vortices strongly depends on vortex density and frequency of the driving current. Depending on the density, we distinguish a single-vortex rectification regime (for low density, when each vortex is rectified individually) determined by the potential-energy landscape inside each cell of the channel (i.e., hard and easy directions) and multi-vortex, or collective, rectification (high-density case) when the inter-vortex interaction becomes important. We analyze the average angular velocity ω of vortices as a function of I and study commensurability effects between the numbers of vortices and cells in the channel and the role of frequency of the applied ac current. We have shown that the commensurability effect results in a stepwise ω-I curve. Besides the integer steps, i.e., the large steps found in the single-vortex case, we also found fractional steps corresponding to fractional ratios between the numbers of vortices and triangular cells. We have performed preliminary measurements on a device containing a single weak-pinning circular ratchet channel in a Corbino geometry and observed a substantial asymmetric vortex response. | ||||
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| Language | Wos | 000295795500010 | Publication Date | 2011-10-07 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 27 | Open Access | |
| Notes | ; We thank Peter Kes and Marcel Hesselberth for providing the superconducting films from which the Corbino ratchet sample was fabricated. This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-Vl (Belgium). T. W. H., K.Y., and B. L. T. P acknowledge support from the National Science Foundation under Grant DMR-0547147 as well as the use of the Cornell NanoScale Facility, a member of the National Nanotechnology Infrastructure Network, which is supported by the National Science Foundation (Grant ECS-0335765). ; | Approved | Most recent IF: 3.836; 2011 IF: 3.691 | ||
| Call Number | UA @ lucian @ c:irua:92809 | Serial | 2848 | ||
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| Author | Sofo, J.O.; Suarez, A.M.; Usaj, G.; Cornaglia, P.S.; Hernández-Nieves, A.D.; Balseiro, C.A. | ||||
| Title | Electrical control of the chemical bonding of fluorine on graphene | Type | A1 Journal article | ||
| Year | 2011 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 83 | Issue | 8 | Pages | 081411 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the electronic structure of diluted F atoms chemisorbed on graphene using density functional theory calculations. We show that the nature of the chemical bonding of a F atom adsorbed on top of a C atom in graphene strongly depends on carrier doping. In neutral samples the F impurities induce a sp(3)-like bonding of the C atom below, generating a local distortion of the hexagonal lattice. As the graphene is electron-doped, the C atom retracts back to the graphene plane and for high doping (10(14) cm(-2)) its electronic structure corresponds to a nearly pure sp(2) configuration. We interpret this sp(3)-sp(2) doping-induced crossover in terms of a simple tight-binding model and discuss the physical consequences of this change. | ||||
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| Language | Wos | 000287484800005 | Publication Date | 2011-02-18 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 65 | Open Access | |
| Notes | ; J.O.S. and A. S. acknowledge support from the Donors of the American Chemical Society Petroleum Research Fund and use of facilities at the Penn State Materials Simulation Center. G. U., P. S. C., A. D. H., and C. A. B. acknowledge financial support from PICTs 06-483 and 2008-2236 from ANPCyT and PIP 11220080101821 from CONICET, Argentina. A. D. H. acknowledges support from the Flemish Science Foundation (FWO). ; | Approved | Most recent IF: 3.836; 2011 IF: 3.691 | ||
| Call Number | UA @ lucian @ c:irua:105600 | Serial | 892 | ||
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| Author | Zhang, S.H.; Xu, W.; Peeters, F.M.; Badalyan, S.M. | ||||
| Title | Electron energy and temperature relaxation in graphene on a piezoelectric substrate | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 89 | Issue | 19 | Pages | 195409 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the energy and temperature relaxation of electrons in graphene on a piezoelectric substrate. Scattering from the combined potential of extrinsic piezoelectric surface acoustical (PA) phonons of the substrate and intrinsic deformation acoustical phonons of graphene is considered for a (non) degenerate gas of Dirac fermions. It is shown that in the regime of low energies or temperatures the PA phonons dominate the relaxation and change qualitatively its character. This prediction is relevant for quantum metrology and electronic applications using graphene devices and suggests an experimental setup for probing electron-phonon coupling in graphene. | ||||
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| Language | Wos | 000336000400008 | Publication Date | 2014-05-09 | |
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| ISSN | 1098-0121;1550-235X; | 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 supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. ; | Approved | Most recent IF: 3.836; 2014 IF: 3.736 | ||
| Call Number | UA @ lucian @ c:irua:117675 | Serial | 928 | ||
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| Author | Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. | ||||
| Title | Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 24 | Pages | 245410 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < |km + 1/2|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > |km + 1/2|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity. | ||||
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| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000403072400005 | Publication Date | 2017-06-13 | |
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| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 13 | Open Access | |
| Notes | ; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:144197 | Serial | 4661 | ||
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| Author | Vodolazov, D.Y.; Peeters, F.M. | ||||
| Title | Strong influence of nonlocal nonequilibrium effects on the dynamics of the order parameter in a phase-slip center: ring studies | Type | A1 Journal article | ||
| Year | 2010 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 81 | Issue | 18 | Pages | 184521,1-184521,7 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the influence of the inelastic relaxation time τ̃E of the quasiparticle distribution function f(E) on the phase slip process in quasi-one-dimensional superconducting rings at a temperature close to the critical temperature Tc. We find that the initial time of growth of the order parameter |Δ| in the phase slip core after the phase slip is a nonmonotonic function of τ̃E which has a maximum at τ̃E≃τ̃GL=πℏ/8kB(Tc−T) and has a tendency to saturate for large τ̃E⪢τ̃GL. The effective heating of the electron subsystem due to the increase in |Δ| in the phase slip center together with the above effect result in a nonmonotonic dependence of the number of subsequent phase slips on τ̃E in rings of relatively large radius (in which each phase slip reduces the current density to a small fraction of its initial value). During the phase slip process the order parameter distribution has two peaks near the phase slip core due to the diffusion of the nonequilibrium quasiparticles from that region. | ||||
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| Language | Wos | 000278141800100 | Publication Date | 2010-05-19 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 5 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). D.Y.V. also acknowledges support from the Russian Foundation for Basic Research, Federal Target Programme “Scientific and scientific-pedagogical personnel of innovative Russia in 2009-2013” and Dynasty Foundation. ; | Approved | Most recent IF: 3.836; 2010 IF: 3.774 | ||
| Call Number | UA @ lucian @ c:irua:83305 | Serial | 3182 | ||
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| Author | Zhang, S.H.; Xu, W.; Badalyan, S.M.; Peeters, F.M. | ||||
| Title | Piezoelectric surface acoustical phonon limited mobility of electrons in graphene on a GaAs substrate | Type | A1 Journal article | ||
| Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 87 | Issue | 7 | Pages | 075443-75445 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the mobility of Dirac fermions in monolayer graphene on a GaAs substrate, limited by the combined action of the extrinsic potential of piezoelectric surface acoustical phonons of GaAs (PA) and of the intrinsic deformation potential of acoustical phonons in graphene (DA). In the high-temperature (T) regime, the momentum relaxation rate exhibits the same linear dependence on T but different dependencies on the carrier density n, corresponding to the mobility mu proportional to 1 root n and 1/n, respectively for the PA and DA scattering mechanisms. In the low-T Bloch-Gruneisen regime, the mobility shows the same square-root density dependence mu proportional to root n, but different temperature dependencies mu proportional to T-3 and T-4, respectively for PA and DA phonon scattering. DOI: 10.1103/PhysRevB.87.075443 | ||||
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| Language | Wos | 000315375200008 | Publication Date | 2013-02-27 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 25 | Open Access | |
| Notes | ; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
| Call Number | UA @ lucian @ c:irua:107655 | Serial | 2622 | ||
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| Author | Jiang, J.; Wang, Y.-L.; Milošević, M.V.; Xiao, Z.-L.; Peeters, F.M.; Chen, Q.-H. | ||||
| Title | Reversible ratchet effects in a narrow superconducting ring | Type | A1 Journal article | ||
| Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 103 | Issue | 1 | Pages | 014502 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the ratchet effect in a narrow pinning-free superconductive ring based on time-dependent Ginzburg-Landau (TDGL) equations. Voltage responses to external dc and ac currents at various magnetic fields are studied. Due to asymmetric barriers for flux penetration and flux exit in the ring-shaped superconductor, the critical current above which the flux-flow state is reached, as well as the critical current for the transition to the normal state, are different for the two directions of applied current. These effects cooperatively cause ratchet signal reversal at high magnetic fields, which has not been reported to date in a pinning-free system. The ratchet signal found here is larger than those induced by asymmetric pinning potentials. Our results also demonstrate the feasibility of using mesoscopic superconductors to employ a superconducting diode effect in versatile superconducting devices. | ||||
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| Language | Wos | 000604821500003 | Publication Date | 2021-01-05 | |
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| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 4 | Open Access | OpenAccess |
| Notes | ; We are grateful to G. Berdiyorov for useful suggestions and comments. Q.-H.C. thanks Beiyi Zhu for helpful discussions during the early stage of this work. This work is supported in part by the National Key Research and Development Program of China, Grants No. 2017YFA0303002 (Q.-H.C. and J.J.), and No. 2018YFA0209002 (Y.-L.W.), and the National Natural Science Foundation of China Grants No. 11834005, No. 11674285, No. 61771235, and No. 61727805. Z.-L.X. acknowledges support by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering and the National Science Foundation under Grant No. DMR-1901843. F.M.P. and M.V.M. acknowledge support by the Research Foundation – Flanders (FWO). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ admin @ c:irua:174984 | Serial | 6697 | ||
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| Author | Piacente, G.; Hai, G.Q.; Peeters, F.M. | ||||
| Title | Continuous structural transitions in quasi-one-dimensional classical Wigner crystals | Type | A1 Journal article | ||
| Year | 2010 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 81 | Issue | 2 | Pages | |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study the structural phase transitions in confined systems of strongly interacting particles. We consider infinite quasi-one-dimensional systems with different pairwise repulsive interactions in the presence of an external confinement following a power law. Within the framework of Landaus theory, we find the necessary conditions to observe continuous transitions and demonstrate that the only allowed continuous transition is between the single- and the double-chain configurations and that it only takes place when the confinement is parabolic. We determine analytically the behavior of the system at the transition point and calculate the critical exponents. Furthermore, we perform Monte Carlo simulations and find a perfect agreement between theory and numerics. | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000274002100035 | Publication Date | 2010-01-19 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 37 | Open Access | |
| Notes | ; The authors acknowledge FAPESP and CNPq (Brazil), the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl) (Belgium) for financial support. ; | Approved | Most recent IF: 3.836; 2010 IF: 3.774 | ||
| Call Number | UA @ lucian @ c:irua:81243 | Serial | 493 | ||
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| Author | Pogosov, W.V.; Misko, V.R.; Zhao, H.J.; Peeters, F.M. | ||||
| Title | Collective vortex phases in periodic plus random pinning potential | Type | A1 Journal article | ||
| Year | 2009 | Publication | Physical review : B : solid state | Abbreviated Journal | Phys Rev B |
| Volume | 79 | Issue | 1 | Pages | 014504,1-014504,12 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study theoretically the simultaneous effect of regular and random pinning potentials on the vortex lattice structure at filling factor of 1. This structure is determined by a competition between the square symmetry of regular pinning array, by the intervortex interaction favoring a triangular symmetry, and by the randomness trying to depin vortices from their regular positions. Both analytical and molecular-dynamics approaches are used. We construct a phase diagram of the system in the plane of regular and random pinning strengths and determine typical vortex lattice defects appearing in the system due to the disorder. We find that the total disordering of the vortex lattice can occur either in one step or in two steps. For instance, in the limit of weak pinning, a square lattice of pinned vortices is destroyed in two steps. First, elastic chains of depinned vortices appear in the film; but the vortex lattice as a whole remains still pinned by the underlying square array of regular pinning sites. These chains are composed into fractal-like structures. In a second step, domains of totally depinned vortices are generated and the vortex lattice depins from regular array. | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000262977900092 | Publication Date | 2009-01-06 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 14 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2009 IF: 3.475 | |||
| Call Number | UA @ lucian @ c:irua:75982 | Serial | 386 | ||
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| Author | Tahir, M.; Vasilopoulos, P.; Peeters, F.M. | ||||
| Title | Quantum magnetotransport properties of a MoS2 monolayer | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 93 | Issue | 93 | Pages | 035406 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study transport properties of a MoS2 monolayer in the presence of a perpendicular magnetic field B. We derive and discuss its band structure and take into account spin and valley Zeeman effects. Compared to a conventional two-dimensional electron gas, these effects lead to new quantum Hall plateaus and new peaks in the longitudinal resistivity as functions of the magnetic field. The field B leads to a significant enhancement of the spin splitting in the conduction band, to a beating of the Shubnikov-de Haas (SdH) oscillations in the low-field regime, and to their splitting in the high-field regime. The Zeeman fields suppress significantly the beating of the SdH oscillations in the low-field regime and strongly enhance their splitting at high fields. The spin and valley polarizations show a similar beating pattern at low fields and are clearly separated at high fields in which they attain a value higher than 90%. | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000367663500003 | Publication Date | 2016-01-05 | |
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| ISSN | 1098-0121; 1550-235x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 42 | Open Access | |
| Notes | ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:131093 | Serial | 4233 | ||
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| Author | Zalipaev, V.; Linton, C.M.; Croitoru, M.D.; Vagov, A. | ||||
| Title | Resonant tunneling and localized states in a graphene monolayer with a mass gap | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 91 | Issue | 91 | Pages | 085405 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We study tunneling of quasiparticles through potential barriers in a graphene monolayer with the mass gap using a semiclassical (WKB) approach. The main equations are derived in away similar to the WKB theory for the Schrodinger equation, which allows for explicit solutions at all orders. The analog of the classical action is used to distinguish types of possible stationary states in the system. The analysis focuses on the resonant scattering and the hole states localized in the vicinity of a barrier that are often overlooked. The scattering coefficients for the physically interesting limits are obtained by matching the WKB approximation with the known solutions at turning points. The localized states demonstrate unconventional properties and lead to alterations of the single particle density of states. | ||||
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| Language | Wos | 000351773900004 | Publication Date | 2015-02-05 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 3 | Open Access | |
| Notes | ; M.D.C. acknowledges the Belgian Science Policy (BELSPO Back to Belgium Grant). ; | Approved | Most recent IF: 3.836; 2015 IF: 3.736 | ||
| Call Number | c:irua:125523 | Serial | 2891 | ||
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| Author | de Sousa, A.A.; Chaves, A.; Farias, G.A.; Peeters, F.M. | ||||
| Title | Braess paradox at the mesoscopic scale | Type | A1 Journal article | ||
| Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 88 | Issue | 24 | Pages | 245417-6 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We theoretically demonstrate that the transport inefficiency recently found experimentally for branched-out mesoscopic networks can also be observed in a quantum ring of finite width with an attached central horizontal branch. This is done by investigating the time evolution of an electron wave packet in such a system. Our numerical results show that the conductivity of the ring does not necessary improve if one adds an extra channel. This ensures that there exists a quantum analog of the Braess paradox, originating from quantum scattering and interference. | ||||
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| Language | Wos | 000328680500011 | Publication Date | 2013-12-17 | |
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| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 17 | Open Access | |
| Notes | ; This work was financially supported by PRONEX/CNPq/FUNCAP and the bilateral project CNPq-FWO. Discussions with J. S. Andrade, Jr. are gratefully acknowledged. A. A. S. has been financially supported by CAPES, under PDSE Contract No. BEX 7177/13-5. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
| Call Number | UA @ lucian @ c:irua:113705 | Serial | 253 | ||
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| Author | Moura, V.N.; Dantas, D.S.; Farias, G.A.; Chaves, A.; Milošević, M.V. | ||||
| Title | Latent superconductivity at parallel interfaces in a superlattice dominated by another collective quantum phase | Type | A1 Journal article | ||
| Year | 2022 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 106 | Issue | 1 | Pages | 014516-10 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We theoretically examine behavior of superconductivity at parallel interfaces separating the domains of another dominant collective excitation, such as charge density waves or spin density waves. Due to their competitive coupling in a two-component Ginzburg-Landau model, suppression of the dominant order parameter at the interfacial planes allows for nucleation of the (hidden) superconducting order parameter at those planes. In such a case, we demonstrate how the number of the parallel interfacial planes and the distance between them are linked to the number and the size of the emerging superconducting gaps in the system, as well as the versatility and temperature evolution of the possible superconducting phases. These findings bear relevance to a broad selection of known layered superconducting materials, as well as to further design of artificial (e.g., oxide) superlattices, where the interplay between competing order parameters paves the way towards otherwise unattainable superconducting states, some with enhanced superconducting critical temperature. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000834346000004 | Publication Date | 2022-07-22 | |
| 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 | |
| Impact Factor | 3.7 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 3.7 | |||
| Call Number | UA @ admin @ c:irua:189520 | Serial | 7179 | ||
| Permanent link to this record | |||||
| Author | Vodolazov, D.Y.; Peeters, F.M. | ||||
| Title | Enhancement of the retrapping current of superconducting microbridges of finite length | Type | A1 Journal article | ||
| Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 85 | Issue | 2 | Pages | 024508-024508,6 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We theoretically find that the resistance of a superconducting microbridge or nanowire decreases while the retrapping current I(r) for the transition to the superconducting state increases when one suppresses the magnitude of the order parameter vertical bar Delta vertical bar in the attached superconducting leads. This effect is a consequence of the increased energy interval for diffusion of the “hot” nonequilibrium quasiparticles (induced by the oscillations of vertical bar Delta vertical bar in the center of the microbridge) to the leads. The effect is absent in short microbridges (with length less than the coherence length) and it is relatively weak in long microbridges (with length larger than the inelastic relaxation length of the nonequilibrium distribution function). A nonmonotonous dependence of I(r) on the length of the microbridge is predicted. Our results are important for the explanation of the enhancement of the critical current and the appearance of negative magnetoresistance observed in many recent experiments on superconducting microbridges or nanowires. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000298863400005 | Publication Date | 2012-01-06 | |
| 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 | 7 | Open Access | |
| Notes | ; This work was supported by the Russian Foundation for Basic Research, Russian Agency of Education, under the Federal Target Programme “Scientific and Educational Personnel of Innovative Russia in 2009-2013” and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | ||
| Call Number | UA @ lucian @ c:irua:96235 | Serial | 1065 | ||
| Permanent link to this record | |||||
| Author | De Beule, C.; Ziani, N.T.; Zarenia, M.; Partoens, B.; Trauzettel, B. | ||||
| Title | Correlation and current anomalies in helical quantum dots | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 94 | Issue | 94 | Pages | 155111 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We theoretically investigate the ground-state properties of a quantum dot defined on the surface of a strong three-dimensional time-reversal invariant topological insulator. Confinement is realized by ferromagnetic barriers and Coulomb interaction is treated numerically for up to seven electrons in the dot. Experimentally relevant intermediate interaction strengths are considered. The topological origin of the dot has several consequences: (i) spin polarization increases and the ground state exhibits quantum phase transitions at specific angular momenta as a function of interaction strength, (ii) the onset of Wigner correlations takes place mainly in one spin channel, and (iii) the ground state is characterized by a robust persistent current that changes sign as a function of the distance from the center of the dot. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000385242200001 | Publication Date | 2016-10-07 | |
| 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 | 3 | Open Access | |
| Notes | ; We thank F. Cavaliere, F. Crepin, C. Felser, and B. Yan for interesting discussions, and S. Curreli for performing the finite-element calculation of the magnetic field in COMSOL. C.D.B. and M.Z. are supported by the Flemish Research Foundation (FWO). N.T.Z. and B.T. acknowledge financial support by the DFG (SPP1666 and SFB1170 “ToCoTronics”), the Helmholtz Foundation (VITI), and the ENB Graduate School on “Topological Insulators.” ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:137234 | Serial | 4351 | ||
| Permanent link to this record | |||||
| Author | Li, L.L.; Xu, W.; Peeters, F.M. | ||||
| Title | Intrinsic optical anisotropy of [001]-grown short-period InAs/GaSb superlattices | Type | A1 Journal article | ||
| Year | 2010 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 82 | Issue | 23 | Pages | 235422-235422,10 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We theoretically investigate the intrinsic optical anisotropy or polarization induced by the microscopic interface asymmetry (MIA) in no-common-atom (NCA) InAs/GaSb superlattices (SLs) grown along the [001] direction. The eight-band K⋅P model is used to calculate the electronic band structures and incorporates the MIA effect. A Boltzmann equation approach is employed to calculate the optical properties. We found that in NCA InAs/GaSb SLs, the MIA effect causes a large in-plane optical anisotropy for linearly polarized light and the largest anisotropy occurs for light polarized along the [110] and [11̅ 0] directions. The relative difference between the optical-absorption coefficient for [110]-polarized light and that for [11̅ 0]-polarized light is found to be larger than 50%. The dependence of the in-plane optical anisotropy on temperature, photoexcited carrier density, and layer width is examined in detail. This study is important for optical devices which require the polarization control and selectivity. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000286768800007 | Publication Date | 2010-12-13 | |
| 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 | 18 | Open Access | |
| Notes | ; This work was supported partly by the Flemish Science Foundation (FWO-VL), the Belgium Science Policy (IAP), the NSF of China (Grants No. 10664006, No. 10504036, and No. 90503005), Special Funds of 973 Project of China (Grant No. 2005CB623603), and Knowledge Innovation Program of the Chinese Academy of Sciences. ; | Approved | Most recent IF: 3.836; 2010 IF: 3.774 | ||
| Call Number | UA @ lucian @ c:irua:88909 | Serial | 1717 | ||
| Permanent link to this record | |||||
| Author | Van der Donck, M.; Peeters, F.M. | ||||
| Title | Rich many-body phase diagram of electrons and holes in doped monolayer transition metal dichalcogenides | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 98 | Issue | 11 | Pages | 115432 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We use a variational technique to study the many-body phase diagram of electrons and holes in n-doped and p-doped monolayer transition metal dichalcogenides (TMDs). We find a total of four different phases. (i) A fully spin polarized and valley polarized ferromagnetic state. (ii) A state with no global spin polarization but with spin polarization in each valley separately, i.e., spin-valley locking. (iii) A state with spin polarization in one of the valleys and little to no spin polarization in the other valley. (iv) A paramagnetic state with no valley polarization. These phases are separated by first-order phase transitions and are determined by the particle density and the dielectric constant of the substrate. We find that in the presence of a perpendicular magnetic field the four different phases persist. In the case of n-doped MoS2, a fifth phase, which is completely valley polarized but not spin polarized, appears for magnetic fields larger than 7 T and for magnetic fields larger than 23 T completely replaces the second phase. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000445507000009 | Publication Date | 2018-09-24 | |
| 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 | 8 | Open Access | |
| Notes | ; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:153622UA @ admin @ c:irua:153622 | Serial | 5125 | ||
| Permanent link to this record | |||||
| Author | Sarmadian, N.; Saniz, R.; Lamoen, D.; Partoens, B. | ||||
| Title | Influence of Al concentration on the optoelectronic properties of Al-doped MgO | Type | A1 Journal article | ||
| Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 86 | Issue | 20 | Pages | 205129-5 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract |
We use density functional theory within the local density approximation to investigate the structural, electronic, and optical properties of Al-doped MgO. The concentrations considered range from 6% to 56%. In the latter case, we also compare the optical properties of the amorphous and crystalline phases. We find that, overall, the electronic properties of the crystalline phases change qualitatively little with Al concentration. On the other hand, the changes in the electronic structure in the amorphous phase are more important, most notably because of deep impurity levels in the band gap that are absent in the crystalline phase. This leads to observable effects in, e.g., the optical absorption edge and in the refractive index. Thus, the latter can be used to characterize the crystalline to amorphous transition with Al doping level. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000311605000003 | Publication Date | 2012-11-28 | |
| 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 | 5 | Open Access | |
| Notes | Iwt; Fwo | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | ||
| Call Number | UA @ lucian @ c:irua:105137 | Serial | 1612 | ||
| Permanent link to this record | |||||
| Author | Li, Z.; Covaci, L.; Berciu, M.; Baillie, D.; Marsiglio, F. | ||||
| Title | Impact of spin-orbit coupling on the Holstein polaron | Type | A1 Journal article | ||
| Year | 2011 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 83 | Issue | 19 | Pages | 195104-195104,9 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We utilize an exact variational numerical procedure to calculate the ground state properties of a polaron in the presence of a Rashba-like spin-orbit interaction. Our results corroborate previous work performed with the momentum average approximation and with weak-coupling perturbation theory. We find that spin-orbit coupling increases the effective mass in the regime with weak electron-phonon coupling, and decreases the effective mass in the regimes of intermediate and strong electron-phonon coupling. Analytical strong-coupling perturbation theory results confirm our numerical results in the small-polaron regime. A large amount of spin-orbit coupling can lead to a significant lowering of the polaron effective mass. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000290162500001 | Publication Date | 2011-05-03 | |
| 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 | 9 | Open Access | |
| Notes | ; This work was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC), by ICORE (Alberta), by Alberta Ingenuity, by the Flemish Science Foundation (FWO-Vl), and by the Canadian Institute for Advanced Research (CIfAR). ; | Approved | Most recent IF: 3.836; 2011 IF: 3.691 | ||
| Call Number | UA @ lucian @ c:irua:89718 | Serial | 1561 | ||
| Permanent link to this record | |||||
| Author | Li, Z.; Covaci, L.; Marsiglio, F. | ||||
| Title | Impact of Dresselhaus versus Rashba spin-orbit coupling on the Holstein polaron | Type | A1 Journal article | ||
| Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 85 | Issue | 20 | Pages | 205112-205112,5 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
We utilize an exact variational numerical procedure to calculate the ground-state properties of a polaron in the presence of Rashba and linear Dresselhaus spin-orbit coupling. We find that when the linear Dresselhaus spin-orbit coupling approaches the Rashba spin-orbit coupling, the Van Hove singularity in the density of states will be shifted away from the bottom of the band and finally disappear when the two spin-orbit couplings are tuned to be equal. The effective mass will be suppressed; the trend will become more significant for low phonon frequency. The presence of two dominant spin-orbit couplings will make it possible to tune the effective mass with more varied observables. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000303794900003 | Publication Date | 2012-05-09 | |
| 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 | 18 | Open Access | |
| Notes | ; This work was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC), by ICORE (Alberta), by the Flemish Science Foundation (FWO-Vl), and by the Canadian Institute for Advanced Research (CIfAR). ; | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | ||
| Call Number | UA @ lucian @ c:irua:99121 | Serial | 1558 | ||
| Permanent link to this record | |||||
| Author | Bercx, M.; Partoens, B.; Lamoen, D. | ||||
| Title | Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors | Type | A1 Journal article | ||
| Year | 2019 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 99 | Issue | 8 | Pages | 085413 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract |
When slow ions incident on a surface are neutralized, the excess potential energy is passed on to an electron inside the surface, leading to emission of secondary electrons. The microscopic description of this process, as well as the calculation of the secondary electron yield, is a challenging problem due to its complexity as well as its sensitivity to surface properties. One of the first quantitative descriptions was articulated in the 1950s by Hagstrum, who based his calculation on a parametrization of the density of states of the material. In this paper, we present a model for calculating the secondary electron yield, derived from Hagstrum’s initial approach. We use first-principles density functional theory calculations to acquire the necessary input and introduce the concept of electron cascades to Hagstrum’s model in order to improve the calculated spectra, as well as remove its reliance on fitting parameters. We apply our model to He+ and Ne+ ions incident on Ge(111) and Si(111) and obtain yield spectra that match closely to the experimental results of Hagstrum. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000458367800010 | Publication Date | 2019-02-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| 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 | 5 | Open Access | OpenAccess |
| Notes | We would like to thank Prof. D. Depla for the useful discussions on the secondary electron yield. Furthermore, we acknowledge financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWOVlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 3.836 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:157174 | Serial | 5154 | ||
| Permanent link to this record | |||||
| Author | Mulkers, J.; Milošević, M.V.; Van Waeyenberge, B. | ||||
| Title | Cycloidal versus skyrmionic states in mesoscopic chiral magnets | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 93 | Issue | 93 | Pages | 214405 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
When subjected to the interfacially induced Dzyaloshinskii-Moriya interaction, the ground state in thin ferromagnetic films with high perpendicular anisotropy is cycloidal. The period of this cycloidal state depends on the strength of the Dzyaloshinskii-Moriya interaction. In this work, we have studied the effect of confinement on the magnetic ground state and excited states, and we determined the phase diagram of thin strips and thin square platelets by means of micromagnetic calculations. We show that multiple cycloidal states with different periods can be stable in laterally confined films, where the period of the cycloids does not depend solely on the Dzyaloshinskii-Moriya interaction strength but also on the dimensions of the film. The more complex states comprising skyrmions are also found to be stable, though with higher energy. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000377298600006 | Publication Date | 2016-06-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| 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 | 28 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 3.836 | ||
| Call Number | c:irua:133919 | Serial | 4081 | ||
| Permanent link to this record | |||||
| Author | Xu, W.; Peeters, F.M.; Devreese, J.T. | ||||
| 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. | ||||
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| 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 | ||
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| Author | Doria, M.M.; Brandt, E.H.; Peeters, F.M. | ||||
| Title | Magnetization of a superconducting film in a perpendicular magnetic field | Type | A1 Journal article | ||
| Year | 2008 | Publication | Physical review : B : solid state | Abbreviated Journal | Phys Rev B |
| Volume | 78 | Issue | 5 | Pages | 0544047,1-054407,7 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
With large thin superconducting films in a perpendicular magnetic field, the usual definition and calculation of the magnetization M via currents or as the difference of two fields fail, since the spatially averaged magnetic field in the film coincides with the uniform applied field and the demagnetization factor is unity. The definition of M as field-derivative of the free energy, however, still works in this limit. We generalize the virial theorem, previously derived for infinite bulk superconductors, to infinitely extended films of arbitrary thickness. An expression for M is obtained that indeed reproduces the M computed from the field derivative of the free energy. | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000259368200063 | Publication Date | 2008-08-08 | |
| 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 | 12 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2008 IF: 3.322 | |||
| Call Number | UA @ lucian @ c:irua:76525 | Serial | 1895 | ||
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| Author | Zarenia, M.; Pereira, J.M.; Chaves, A.; Peeters, F.M.; Farias, G.A. | ||||
| Title | Simplified model for the energy levels of quantum rings in single layer and bilayer graphene | Type | A1 Journal article | ||
| Year | 2010 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 81 | Issue | 4 | Pages | 045431,1-045431,9 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
Within a minimal model, we present analytical expressions for the eigenstates and eigenvalues of carriers confined in quantum rings in monolayer and bilayer graphene. The calculations were performed in the context of the continuum model by solving the Dirac equation for a zero width ring geometry, i.e., by freezing out the carrier radial motion. We include the effect of an external magnetic field and show the appearance of Aharonov-Bohm oscillations and of a nonzero gap in the spectrum. Our minimal model gives insight on the energy spectrum of graphene-based quantum rings and models different aspects of finite width rings. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000277186000010 | Publication Date | 2010-01-29 | |
| 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 | 76 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the Bilateral program between Flanders and Brazil, and the Brazilian Council for Research (CNPq). ; | Approved | Most recent IF: 3.836; 2010 IF: 3.774 | ||
| Call Number | UA @ lucian @ c:irua:82866 | Serial | 3005 | ||
| Permanent link to this record | |||||
| Author | da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. | ||||
| Title | Energy levels of bilayer graphene quantum dots | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 92 | Issue | 92 | Pages | 115437 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
Within a tight binding approach we investigate the energy levels of hexagonal and triangular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We study AA- and AB-(Bernal) stacked BLG QDs and obtain the energy levels in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). Our results show that the size dependence of the energy levels is different from that of monolayer graphene QDs. The energy spectrum of AB-stacked BLG QDs with zigzag edges exhibits edge states which spread out into the opened energy gap in the presence of a perpendicular electric field. We found that the behavior of these edges states is different for the hexagonal and triangular geometries. In the case of AA-stacked BLG QDs, the electron and hole energy levels cross each other in both cases of armchair and zigzag edges as the dot size or the applied bias increases. | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000361663700003 | Publication Date | 2015-09-24 | |
| 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 | 21 | Open Access | |
| Notes | ; This work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the process number BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; | Approved | Most recent IF: 3.836; 2015 IF: 3.736 | ||
| Call Number | UA @ lucian @ c:irua:128726 | Serial | 4173 | ||
| Permanent link to this record | |||||
| Author | Mirzakhani, M.; Peeters, F.M.; Zarenia, M. | ||||
| Title | Circular quantum dots in twisted bilayer graphene | Type | A1 Journal article | ||
| Year | 2020 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 101 | Issue | 7 | Pages | 075413 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
Within a tight-binding approach, we investigate the effect of twisting angle on the energy levels of circular bilayer graphene (BLG) quantum dots (QDs) in both the absence and presence of a perpendicular magnetic field. The QDs are defined by an infinite-mass potential, so that the specific edge effects are not present. In the absence of magnetic field (or when the magnetic length is larger than the moire length), we show that the low-energy states in twisted BLG QDs are completely affected by the formation of moire patterns, with a strong localization at AA-stacked regions. When magnetic field increases, the energy gap of an untwisted BLG QD closes with the edge states, localized at the boundaries between the AA- and AB-stacked spots in a twisted BLG QD. Our observation of the spatial localization of the electrons in twisted BLG QDs can be experimentally probed by low-bias scanning tunneling microscopy measurements. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000512772200004 | Publication Date | 2020-02-13 | |
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| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.7 | Times cited | 19 | Open Access | |
| Notes | ; We gratefully acknowledge discussions with I. Snyman. M.Z. acknowledges support from the U.S. Department of Energy (Office of Science) under Grant No. DE-FG0205ER46203. ; | Approved | Most recent IF: 3.7; 2020 IF: 3.836 | ||
| Call Number | UA @ admin @ c:irua:166493 | Serial | 6470 | ||
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| Author | Liu, C.-Y.; Berdiyorov, G.R.; Milošević, M.V. | ||||
| Title | Vortex states in layered mesoscopic superconductors | Type | A1 Journal article | ||
| Year | 2011 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 83 | Issue | 10 | Pages | 104524-104524,10 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
Within the Ginzburg-Landau theory, we study the vortex structures in three-dimensional anisotropic mesoscopic superconductors in the presence of a uniform magnetic field. Anisotropy is included through varied Tc in different layers of the sample and leads to distinct differences in the vortex states and their free energy. Several unconventional states are found, some comprising vortex clusters or exhibiting asymmetry. In a tilted magnetic field, we found second-order transitions between different vortex states, although vortex entry is generally a first-order transition in mesoscopic samples. In multilayered samples the kinked vortex strings are formed owing to the competing interactions of vortices with Meissner currents and the weak-link boundaries. The length and deformation of vortex fragments are determined solely by the inclination and strength of applied magnetic field, and this lock-in does not depend on the degree of anisotropy between the superconducting layers. | ||||
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| Language | Wos | 000288998200003 | Publication Date | 2011-03-31 | |
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| 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 | 22 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 3.836; 2011 IF: 3.691 | ||
| Call Number | UA @ lucian @ c:irua:89375 | Serial | 3888 | ||
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| Author | Saberi-Pouya, S.; Vazifehshenas, T.; Salavati-Fard, T.; Farmanbar, M.; Peeters, F.M. | ||||
| Title | Strong anisotropic optical conductivity in two-dimensional puckered structures : the role of the Rashba effect | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 96 | Issue | 7 | Pages | 075411 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract |
within the Kubo formalism. We show that the anisotropic Rashba effect caused by an external field significantly changes the magnitude of the spin splitting. Furthermore, we obtain an analytical expression for the longitudinal optical conductivity associated with interband transitions as a function of the frequency for arbitrary polarization angle. We find that the diagonal components of the optical conductivity tensor are direction dependent and the optical absorption spectrum exhibits a strongly anisotropic absorption window. The height and width of this absorption window are very sensitive to the anisotropy of the system. While the height of absorption peak increases with increasing effective mass anisotropy ratio, the peak intensity is larger when the light polarization is along the armchair direction. Moreover, the absorption peak width becomes broader as the density-of-states mass or Rashba interaction is enhanced. These features in the optical absorption spectrum can be used to determine parameters relevant for spintronics. | ||||
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| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000407097100005 | Publication Date | 2017-08-09 | |
| 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 | 16 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:145725 | Serial | 4752 | ||
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