|
“Geometry-induced localization of thermal fluctuations in ultrathin superconducting structures”. Pogosov WV, Misko VR, Peeters FM, Physical review : B : condensed matter and materials physics 82, 054523 (2010). http://doi.org/10.1103/PhysRevB.82.054523
Abstract: Thermal fluctuations of the order parameter in an ultrathin triangular-shaped superconducting structure are studied near Tc, in zero applied field. We find that the order parameter is prone to much larger fluctuations in the corners of the structure as compared to its interior. This geometry-induced localization of thermal fluctuations is attributed to the fact that condensate confinement in the corners is characterized by a lower effective dimensionality, which favors stronger fluctuations.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 2
DOI: 10.1103/PhysRevB.82.054523
|
|
|
“Optoelectronic properties of graphene in the presence of optical phonon scattering”. Xu W, Dong HM, Li LL, Yao JQ, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 82, 125304 (2010). http://doi.org/10.1103/PhysRevB.82.125304
Abstract: We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 28
DOI: 10.1103/PhysRevB.82.125304
|
|
|
“Spin-orbit interaction controlled properties of two-dimensional superlattices”. Földi P, Szaszkó-Bogár V, Peeters FM, Physical review : B : condensed matter and materials physics 82, 115302 (2010). http://doi.org/10.1103/PhysRevB.82.115302
Abstract: The band structure of two-dimensional artificial superlattices in the presence of (Rashba-type) spin-orbit interaction (SOI) is presented. The position and shape of the energy bands in these spintronic crystals depend on the geometry as well as the strength of the SOI, which can be tuned by external gate voltages. For finite mesoscopic arrays, we show that their conductance properties and possible applications can be understood from these spin-dependent band diagrams.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 6
DOI: 10.1103/PhysRevB.82.115302
|
|
|
“Tuning of the two electron states in quantum rings through the spin-orbit interaction”. Liu Y, Cheng F, Li XJ, Peeters FM, Chang K, Physical review : B : condensed matter and materials physics 82, 1 (2010). http://doi.org/10.1103/PhysRevB.82.045312
Abstract: The effect of the Coulomb interaction on the energy spectrum and anisotropic distribution of two electron states in a quantum ring in the presence of Rashba spin-orbit interaction (RSOI) and Dresselhaus SOI (DSOI) is investigated in the presence of a perpendicular magnetic field. We find that the interplay between the RSOI and DSOI makes the single quantum ring behaves like a laterally coupled quantum dot and the interdot coupling can be tuned by changing the strengths of the SOIs. The interplay can lead to singlet-triplet state mixing and anticrossing behavior when the singlet and triplet states meet with increasing magnetic field. The two electron ground state displays a bar-bell-like spatial anisotropic distribution in a quantum ring at a specific crystallographic direction, i.e., [110] or [11̅ 0], which can be switched by reversing the direction of the perpendicular electric field. The ground state exhibits a singlet-triplet state transition with increasing magnetic field and strengths of RSOI and DSOI. An anisotropic electron distribution is predicted which can be detected through the measurement of its optical properties.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 14
DOI: 10.1103/PhysRevB.82.045312
|
|
|
“The optical excitonic Aharonov-Bohm effect in a few nanometer wide type-I nanorings”. Tadić, M, Arsoski V, Čukarić, N, Peeters FM, Acta physica Polonica: A: general physics, solid state physics, applied physics 117, 974 (2010)
Abstract: The optical excitonic Aharonov-Bohm effect in type-1 three-dimensional (In, Ga)As/GaAs nanorings in theoretically explored. The single-particle states of the electron and the hole are extracted from the effective mass theory in the presence of inhomogeneous strain, and an exact numerical diagonalization approach is used to compute the exciton states and the oscillator strength fx for exciton recombination. We studied both the large lithographically-defined and small self-assembled rings. Only in smaller self-assembled nanorings we found optical excitonic AharonovBohm effect. Those oscillations are established by anticrossings between the optically active exciton states with zero orbital momentum. In lithographically defined rings, whose average radius is 33 nm, fx shows no oscillations, whereas in the smaller self-assembled nanoring with average radius of 11.5 nm oscillations in fx for the ground exciton state are found as function of the magnetic field that is superposed on a linear dependence. These oscillations are smeared out at finite temperature, thus photoluminescence intensity exhibits step-like variation with magnetic field even at temperature as small as 4.2 K.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.469
|
|
|
“Landau-level broadening due to electron-impurity interaction in graphene in strong magnetic fields”. Yang CH, Peeters FM, Xu W, Physical review : B : condensed matter and materials physics 82, 075401:1 (2010). http://doi.org/10.1103/PhysRevB.82.075401
Abstract: The effect of electron-impurity and electron-electron interactions on the energy spectrum of electrons moving in graphene is investigated in the presence of a high magnetic field. We find that the width of the broadened Landau levels exhibits an approximate 1/B dependence near half filling for charged impurity scattering. The Landau-level width, the density of states, and the Fermi energy exhibit an oscillatory behavior as a function of magnetic field. Comparison with experiment shows that scattering with charged impurities cannot be the main scattering mechanism that determines the width of the Landau levels.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 38
DOI: 10.1103/PhysRevB.82.075401
|
|
|
“Gate controlled Aharonov-Bohm-type oscillations from single neutral excitons in quantum rings”. Ding F, Akopian N, Li B, Perinetti U, Govorov A, Peeters FM, Bufon CC, Deneke C, Chen YH, Rastelli A, Schmidt OG, Zwiller V, Physical review : B : condensed matter and materials physics 82, 8 (2010). http://doi.org/10.1103/PhysRevB.82.075309
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 58
DOI: 10.1103/PhysRevB.82.075309
|
|
|
“Vortex matter in mesoscopic two-gap superconducting disks: influence of Josephson and magnetic coupling”. Geurts R, Milošević, MV, Peeters FM, Physical review : B : condensed matter and materials physics 81, 15 (2010). http://doi.org/10.1103/PhysRevB.81.214514
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 89
DOI: 10.1103/PhysRevB.81.214514
|
|
|
“Electric field: A catalyst for hydrogenation of graphene”. Ao ZM, Peeters FM, Applied physics letters 96, 3 (2010). http://doi.org/10.1063/1.3456384
Abstract: Due to the importance of hydrogenation of graphene for several applications, we present an alternative approach to hydrogenate graphene based on density functional theory calculations. We find that a negative perpendicular electric field F can act as a catalyst to reduce the energy barrier for molecular H<sub>2</sub> dissociative adsorption on graphene. Increasing -F above 0.02 a.u. (1 a.u.=5.14×10<sup>11</sup> V/m), this hydrogenation process occurs smoothly without any potential barrier.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 88
DOI: 10.1063/1.3456384
|
|
|
“A two-component mixture of charged particles confined in a channel: melting”. Ferreira WP, Farias GA, Peeters FM, Journal of physics : condensed matter 22, 11 (2010). http://doi.org/10.1088/0953-8984/22/28/285103
Abstract: The melting of a binary system of charged particles confined in a quasi-one-dimensional parabolic channel is studied through Monte Carlo simulations. At zero temperature the particles are ordered in parallel chains. The melting is anisotropic and different melting temperatures are obtained according to the spatial direction, and the different kinds of particles present in the system. Melting is very different for the single-, two- and four-chain configurations. A temperature induced structural phase transition is found between two different four-chain ordered states which is absent in the mono-disperse system. In the mixed regime, where the two kinds of particles are only slightly different, melting is almost isotropic and a thermally induced homogeneous distribution of the distinct kinds of charges is observed.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 10
DOI: 10.1088/0953-8984/22/28/285103
|
|
|
“Linear reduction of stiffness and vibration frequencies in defected circular monolayer graphene”. Neek-Amal M, Peeters FM, Physical review : B : condensed matter and materials physics 81, 11 (2010). http://doi.org/10.1103/PhysRevB.81.235437
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 44
DOI: 10.1103/PhysRevB.81.235437
|
|
|
“Vortex manipulation in a superconducting matrix with view on applications”. Milošević, MV, Peeters FM, Applied physics letters 96, 192501 (2010). http://doi.org/10.1063/1.3425672
Abstract: We show how a single flux quantum can be effectively manipulated in a superconducting film with a matrix of blind holes. Such a sample can serve as a basic memory element, where the position of the vortex in a k×l matrix of pinning sites defines the desired combination of n bits of information (2n = k×l). Vortex placement is achieved by strategically applied current and the resulting position is read out via generated voltage between metallic contacts on the sample. Such a device can also act as a controllable source of a nanoengineered local magnetic field for, e.g., spintronics applications.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 14
DOI: 10.1063/1.3425672
|
|
|
“High-capacity hydrogen storage in Al-adsorbed graphene”. Ao ZM, Peeters FM, Physical review : B : condensed matter and materials physics 81, 205406 (2010). http://doi.org/10.1103/PhysRevB.81.205406
Abstract: A high-capacity hydrogen storage mediumAl-adsorbed grapheneis proposed based on density-functional theory calculations. We find that a graphene layer with Al adsorbed on both sides can store hydrogen up to 13.79 wt % with average adsorption energy −0.193 eV/H2. Its hydrogen storage capacity is in excess of 6 wt %, surpassing U. S. Department of Energy (DOEs) target. Based on the binding-energy criterion and molecular-dynamics calculations, we find that hydrogen storage can be recycled at near ambient conditions. This high-capacity hydrogen storage is due to the adsorbed Al atoms that act as bridges to link the electron clouds of the H2 molecules and the graphene layer. As a consequence, a two-layer arrangement of H2 molecules is formed on each side of the Al-adsorbed graphene layer. The H2 concentration in the hydrogen storage medium can be measured by the change in the conductivity of the graphene layer.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 219
DOI: 10.1103/PhysRevB.81.205406
|
|
|
“Carbon clusters: from ring structures to nanographene”. Kosimov DP, Dzhurakhalov AA, Peeters FM, Physical review : B : condensed matter and materials physics 81, 195414 (2010). http://doi.org/10.1103/PhysRevB.81.195414
Abstract: The lowest-energy configurations of Cn(n≤55) clusters are obtained using the energy-minimization technique with the conjugate gradient method where a modified Brenner potential is invoked to describe the carbon and hydrocarbon interaction. We found that the ground-state configuration consists of a single ring for small number of C atoms and multiring structures are found with increasing n, which can be in planar, bowl-like or caplike form. Contrary to previous predictions, the binding energy Eb does not show even-odd oscillations and only small jumps are found in the Eb(n) curve as a consequence of specific types of edges or equivalently the number of secondary atoms. We found that hydrogenation of the edge atoms may change the ground-state configuration of the nanocluster. In both cases we determined the magic clusters. Special attention is paid to trigonal and hexagonal shaped carbon clusters and to clusters having a graphenelike configuration. Trigonal clusters are never the ground state while hexagonal-shaped clusters are only the ground state when they have zigzag edges.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Integrated Molecular Plant Physiology Research (IMPRES); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.836
Times cited: 55
DOI: 10.1103/PhysRevB.81.195414
|
|
|
“Interband optical properties of concentric type-I nanorings in a normal magnetic field”. Arsoski V, Tadić, M, Peeters FM, Acta physica Polonica: A: general physics, solid state physics, applied physics 117, 733 (2010)
Abstract: Two concentric two-dimensional GaAs/(Al,Ga)As nanorings in a normal magnetic field are theoretically studied. The single-band effective mass approximation is adopted for both the electron and the hole states, and the analytical solutions are given. We find that the electronic single particle states are arranged in pairs, which exhibit anticrossings and the orbital momentum transitions in the energy spectrum when magnetic field increases. Their period is essentially determined by the radius of the outer ring. The oscillator strength for interband transitions is strongly reduced close to each anticrossing. We show that an optical excitonic Aharonov-Bohm effect may occur in concentric nanorings.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 0.469
|
|
|
“Topological confinement in graphene bilayer quantum rings”. Xavier LJP, Pereira JM, Chaves A, Farias GA, Peeters FM, Applied physics letters 96, 212108 (2010). http://doi.org/10.1063/1.3431618
Abstract: We find localized electron and hole states in a ring-shaped potential kink in biased bilayer graphene. Within the continuum description, we show that for sharp potential steps the Dirac equation describing carrier states close to the K (or K′) point of the first Brillouin zone can be solved analytically for a circular kink/antikink dot. The solutions exhibit interfacial states which exhibit AharonovBohm oscillations as functions of the height of the potential step and/or the radius of the ring.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 29
DOI: 10.1063/1.3431618
|
|
|
“Strong influence of nonlocal nonequilibrium effects on the dynamics of the order parameter in a phase-slip center: ring studies”. Vodolazov DY, Peeters FM, Physical review : B : condensed matter and materials physics 81, 184521 (2010). http://doi.org/10.1103/PhysRevB.81.184521
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.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 5
DOI: 10.1103/PhysRevB.81.184521
|
|
|
“Superconducting nanowires: quantum-confinement effect on the critical magnetic field and supercurrent”. Croitoru MD, Shanenko AA, Peeters FM, , 327 (2010). http://doi.org/10.1142/9789814289153_0025
Abstract: We study the effect, of electron confinement on the superconducting-to-normal phase transition driven by a magnetic field and/or on the current-carrying state of the superconducting condensate in nanowires. Our investigation is based on a self-consistent. numerical solution of the Bogoliubov-de Gennes equations. We show that, in a parallel magnetic field and/or in the presence of supercurrent the transition from superconducting to normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magnetic held exhibits quantum-size oscillations with pronounced resonant enhancements.
Keywords: P1 Proceeding; Condensed Matter Theory (CMT)
DOI: 10.1142/9789814289153_0025
|
|
|
“Nanoindentation of a circular sheet of bilayer graphene”. Neek-Amal M, Peeters FM, Physical review : B : condensed matter and materials physics 81, 235421 (2010). http://doi.org/10.1103/PhysRevB.81.235421
Abstract: Nanoindentation of bilayer graphene is studied using molecular-dynamics simulations. We compared our simulation results with those from elasticity theory as based on the nonlinear Föppl-Hencky equations with rigid boundary condition. The force-deflection values of bilayer graphene are compared to those of monolayer graphene. Youngs modulus of bilayer graphene is estimated to be 0.8 TPa which is close to the value for graphite. Moreover, an almost flat bilayer membrane at low temperature under central load has a 14% smaller Youngs modulus as compared to the one at room temperature.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 108
DOI: 10.1103/PhysRevB.81.235421
|
|
|
“Simplified model for the energy levels of quantum rings in single layer and bilayer graphene”. Zarenia M, Pereira JM, Chaves A, Peeters FM, Farias GA, Physical review : B : condensed matter and materials physics 81, 045431 (2010). http://doi.org/10.1103/PhysRevB.81.045431
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.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 76
DOI: 10.1103/PhysRevB.81.045431
|
|
|
“Vortices induced in a superconducting loop by asymmetric kinetic inductance and their detection in transport measurements”. Berdiyorov GR, Milošević, MV, Peeters FM, Physical review : B : condensed matter and materials physics 81, 144511 (2010). http://doi.org/10.1103/PhysRevB.81.144511
Abstract: Using time-dependent Ginzburg-Landau theory, we study the dynamic properties of a rectangular superconducting loop, which are found to depend on the position of the current leads. For asymmetric positioning of the leads, different kinetic inductance of the two paths for injected electric current leads to different critical conditions in the two branches. System self-regulates by allowing vortex entry, as vortex currents bring equilibration between the two current flows and the conventional resistive state can be realized. We also demonstrate that individual vortex entry in the loop can be detected by measuring the voltage between normal-metal leads, for applied currents comparable in magnitude to the screening currents.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 18
DOI: 10.1103/PhysRevB.81.144511
|
|
|
“Dynamics of multishell vortex structures in mesoscopic superconducting Corbino disks”. Lin NS, Misko VR, Peeters FM, Physical review : B : condensed matter and materials physics 81, 134504 (2010). http://doi.org/10.1103/PhysRevB.81.134504
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.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 11
DOI: 10.1103/PhysRevB.81.134504
|
|
|
“Two kinds of vortex states in thin mesoscopic superconductors”. Baelus BJ, Kanda A, Peeters FM, Ootuka Y, Kadowaki K, Journal of physics : conference series
T2 –, Journal of physics: conference series 43, 647 (2006). http://doi.org/10.1088/1742-6596/43/1/158
Abstract: Experimentally, multivortex states and giant vortex states in mesoscopic superconductors can be distinguished directly by using the multiple-small-tunnel-junctions, and indirectly by studying the temperature dependence of the expulsion fields. These experimental results are compared with the theoretical prediction from the nonlinear Ginzburg- Landau theory.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
DOI: 10.1088/1742-6596/43/1/158
|
|
|
“Formation of vortex clusters and giant vortices in mesoscopic superconducting disks with strong disorder”. Escoffier W, Grigorieva IV, Misko VR, Baelus BJ, Peeters FM, Vinnikov LY, Dubnos S, Journal of physics : conference series 97, 012172 (2008). http://doi.org/10.1088/1742-6596/97/1/012172
Abstract: Merged, or giant, multi-quanta vortices (GVs) appear in very small superconductors near the superconducting transition due to strong confinement of magnetic flux. Here we present evidence for a new, pinning-related, mechanism for vortex merger. Using Bitter decoration to visualise vortices in small Nb disks, we show that confinement in combination with strong disorder causes individual vortices to merge into clusters/GVs well below Tc and Hc2, in contrast to well-defined shells of individual vortices found in the absence of pinning.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
DOI: 10.1088/1742-6596/97/1/012172
|
|
|
“Magnetoresistance in a hybrid ferromagnetic/semiconductor device”. Papp G, Peeters FM, Journal of applied physics 107, 063718 (2010). http://doi.org/10.1063/1.3359652
Abstract: Ballistic transport of a two-dimensional electron gas (2DEG) in a rectangle shaped wire, subjected to a local nonhomogeneous magnetic field that results from an in-plane magnetized ferromagnetic (FM) strip deposited above the 2DEG, is investigated theoretically. We found a positive magnetoresistance (MR), which exhibits hysteresis behavior with respect to the direction of the magnetic field sweep, in agreement with a recent experiment. This positive MR can be tuned by applying a gate voltage to the FM strip.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 10
DOI: 10.1063/1.3359652
|
|
|
“Transport detection of quantum Hall fluctuations in graphene”. Branchaud S, Kam A, Zawadzki P, Peeters FM, Sachrajda AS, Physical review : B : condensed matter and materials physics 81, 121406 (2010). http://doi.org/10.1103/PhysRevB.81.121406
Abstract: Low-temperature magnetoconductance measurements were made in the vicinity of the charge neutrality point (CNP). Two origins for the fluctuations were identified close to the CNP. At very low magnetic fields there exist only mesoscopic magnetoconductance quantum interference features which develop rapidly as a function of density. At slightly higher fields (>0.5 T), close to the CNP, additional fluctuations track the quantum Hall (QH) sequence expected for monolayer graphene. These additional features are attributed to effects of locally charging individual QH localized states. These effects reveal a precursor to the quantum Hall effect since, unlike previous transport observations of QH dot charging effects, they occur in the absence of quantum Hall plateaus or Shubnikov-de Haas oscillations. From our transport data we are able to extract parameters that characterize the inhomogeneities in our device.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 25
DOI: 10.1103/PhysRevB.81.121406
|
|
|
“Stacking order dependent electric field tuning of the band gap in graphene multilayers”. Avetisyan AA, Partoens B, Peeters FM, Physical review : B : condensed matter and materials physics 81, 115432 (2010). http://doi.org/10.1103/PhysRevB.81.115432
Abstract: The effect of different stacking order of graphene multilayers on the electric field induced band gap is investigated. We considered a positively charged top and a negatively charged back gate in order to independently tune the band gap and the Fermi energy of three and four layer graphene systems. A tight-binding approach within a self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We found that the gap for trilayer graphene with the ABC stacking is much larger than the corresponding gap for the ABA trilayer. Also we predict that for four layers of graphene the energy gap strongly depends on the choice of stacking, and we found that the gap for the different types of stacking is much larger as compared to the case of Bernal stacking. Trigonal warping changes the size of the induced electronic gap by approximately 30% for intermediate and large values of the induced electron density.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 142
DOI: 10.1103/PhysRevB.81.115432
|
|
|
“Vortex patterns in a mesoscopic superconducting rod with a magnetic dot”. Doria MM, Romaguera AR de C, Peeters FM, Physical review : B : condensed matter and materials physics 81, 104529 (2010). http://doi.org/10.1103/PhysRevB.81.104529
Abstract: We study a mesoscopic superconducting rod with a magnetic dot on its top having its moment oriented along the axis of symmetry. We study the dependence of the vortex pattern with the height and find that for very short and very long rods, the vortex pattern acquires a simple structure, consisting of giant and of multivortex states, respectively. In the long limit, the most stable configuration consists of two vortices, that reach the lateral surface of the rod diametrically opposed. The long rod shows reentrant behavior within some range of its radius and of the dots magnetic moment. Our results are obtained within the Ginzburg-Landau approach in the limit of no magnetic shielding.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 5
DOI: 10.1103/PhysRevB.81.104529
|
|
|
“Extra Dirac points in the energy spectrum for superlattices on single-layer graphene”. Barbier M, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 81, 075438 (2010). http://doi.org/10.1103/PhysRevB.81.075438
Abstract: We investigate the emergence of extra Dirac points in the electronic structure of a periodically spaced barrier system, i.e., a superlattice, on single-layer graphene, using a Dirac-type Hamiltonian. Using square barriers allows us to find analytic expressions for the occurrence and location of these new Dirac points in k space and for the renormalization of the electron velocity near them in the low-energy range. In the general case of unequal barrier and well widths the new Dirac points move away from the Fermi level and for given heights of the potential barriers there is a minimum and maximum barrier width outside of which the new Dirac points disappear. The effect of these extra Dirac points on the density of states and on the conductivity is investigated.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 211
DOI: 10.1103/PhysRevB.81.075438
|
|
|
“Calorimetric properties of mesoscopic superconducting disks, rings, and cylinders”. Xu B, Milošević, MV, Peeters FM, Physical review : B : condensed matter and materials physics 81, 064501 (2010). http://doi.org/10.1103/PhysRevB.81.064501
Abstract: The thermal signatures of superconductivity in mesoscopic disks, rings and cylinders are calculated within the Ginzburg-Landau theory. In an applied perpendicular magnetic field H the heat capacity of mesoscopic samples shows a strong dependence on the realized vortex state; discontinuities are found at the critical field for different vorticities, as well as at the superconducting-to-normal state transition. The same applies to the intermediate state of type-I superconductors. Even the subtle changes in the fluxoid distribution inside the sample leave clear signatures on heat capacity, which is particularly useful for fully three-dimensional samples whose interior is often inaccessible by magnetometry. The heat-capacity jump ΔC(H) at the critical temperature exhibits quasiperiodic modulations as a function of magnetic field. In mesoscopic superconducting rings, these oscillations provide calorimetric verification of the Little-Parks effect.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 17
DOI: 10.1103/PhysRevB.81.064501
|
|