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Author Vagov, A.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. url  doi
openurl 
  Title Two-band superconductors : extended Ginzburg-Landau formalism by a systematic expansion in small deviation from the critical temperature Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 86 Issue 14 Pages 144514  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We derive the extended Ginzburg-Landau (GL) formalism for a clean s-wave two-band superconductor by employing a systematic expansion of the free-energy functional and the corresponding matrix gap equation in powers of the small deviation from the critical temperature tau = 1 – T/T-c. The two lowest orders of this expansion produce the equation for T-c and the standard GL theory. It is shown that in agreement with previous studies, this two-band GL theory maps onto the single-band GL model and thus fails to describe the difference in the spatial profiles of the two-band condensates. We prove that this difference appears already in the leading correction to the standard GL theory, which constitutes the extended GL formalism. We derive linear differential equations that determine the leading corrections to the band order parameters and magnetic field, discuss the validity of these equations, and consider examples of an important interplay between the band condensates. Finally, we present numerical results for the thermodynamic critical magnetic field and temperature-dependent band gaps for recent materials of interest, which are in very good agreement with those obtained from the full BCS approach in a wide temperature range. To this end, we emphasize the advantages of our extended GL theory in comparison with the often used two-component GL-like model based on an unreconstructed two-band generalization of the Gor'kov derivation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000309776800001 Publication Date 2012-10-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 44 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). Authors are indebted to Y. Singh and R. Prozorov for discussions and for providing recent experimental data. A. V. is grateful to W. Pesch for stimulating discussions and critical comments on this work. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:101798 Serial 3769  
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Author da Costa, D.R.; Chaves, A.; Farias, G.A.; Covaci, L.; Peeters, F.M. url  doi
openurl 
  Title Wave-packet scattering on graphene edges in the presence of a pseudomagnetic field Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 86 Issue 11 Pages 115434  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The scattering of a Gaussian wave packet in armchair and zigzag graphene edges is theoretically investigated by numerically solving the time-dependent Schrodinger equation for the tight-binding model Hamiltonian. Our theory allows us to investigate scattering in reciprocal space, and depending on the type of graphene edge we observe scattering within the same valley, or between different valleys. In the presence of an external magnetic field, the well-known skipping orbits are observed. However, our results demonstrate that in the case of a pseudomagnetic field, induced by nonuniform strain, the scattering by an armchair edge results in a nonpropagating edge state.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000309174100005 Publication Date 2012-09-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 28 Open Access  
  Notes ; Discussions with E. B. Barros are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE (project CONGRAN), and the bilateral program between Flanders and Brazil. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:101833 Serial 3907  
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Author Ramos, I.R.O.; Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Bilayer crystals of charged magnetic dipoles : structure and phonon spectrum Type A1 Journal article
  Year 2012 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E  
  Volume (down) 85 Issue 5:1 Pages 051404-051404,12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study the structure and phonon spectrum of a two-dimensional bilayer system of classical charged dipoles oriented perpendicular to the plane of the layers for equal density in each layer. This system can be tuned through six different crystalline phases by changing the interlayer separation or the charge and/or dipole moment of the particle. The presence of the charge on the dipole particles is responsible for the nucleation of five staggered phases and a disordered phase which are not found in the magnetic dipole bilayer system. These extra phases are a consequence of the competition between the repulsive Coulomb and the attractive dipole interlayer interaction. We present the phase diagram and determine the order of the phase transitions. The phonon spectrum of the system was calculated within the harmonic approximation, and a nonmonotonic behavior of the phonon spectrum is found as a function of the effective strength of the interparticle interaction. The stability of the different phases is determined.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor  
  Language Wos 000304403400002 Publication Date 2012-05-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.366 Times cited 8 Open Access  
  Notes ; This work was supported by the Brazilian agencies CNPq, CAPES, and FUNCAP (PRONEX grant), the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the CNPq-FWO collaborating project. The authors are grateful to Prof. G. Goldoni for some technical clarifications concerning Ref. [18]. ; Approved Most recent IF: 2.366; 2012 IF: 2.313  
  Call Number UA @ lucian @ c:irua:98940 Serial 233  
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Author Carvalho, J.C.N.; Nelissen, K.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Diffusion in a quasi-one-dimensional system on a periodic substrate Type A1 Journal article
  Year 2012 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E  
  Volume (down) 85 Issue 2:1 Pages 021136-021136,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The diffusion of charged particles interacting through a repulsive Yukawa potential, exp(-r/lambda)/r, confined by a parabolic potential in the y direction and subjected to a periodic substrate potential in the x direction is investigated. Langevin dynamic simulations are used to investigate the effect of the particle density, the amplitude of the periodic substrate, and the range of the interparticle interaction potential on the diffusive behavior of the particles. We found that in general the diffusion is suppressed with increasing the amplitude of the periodic potential, but for specific values of the strength of the substrate potential a remarkable increase of the diffusion is found with increasing the periodic potential amplitude. In addition, we found a strong dependence of the diffusion on the specific arrangement of the particles, e. g., single-chain versus multichain configuration. For certain particle configurations, a reentrant behavior of the diffusion is found as a function of the substrate strength due to structural transitions in the ordering of the particles.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor  
  Language Wos 000300671500007 Publication Date 2012-02-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.366 Times cited 9 Open Access  
  Notes ; This work was supported by the Brazilian agencies CNPq and FUNCAP (PRONEX-Grant), the Flemish Science Foundation (FWO-Vl), and the bilateral projects between Flanders and Brazil and the Flemish Science Foundation (FWO-VI) and CNPq. ; Approved Most recent IF: 2.366; 2012 IF: 2.313  
  Call Number UA @ lucian @ c:irua:97203 Serial 698  
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Author Berdiyorov, G.R.; de Romaguera, A.R.C.; Milošević, M.V.; Doria, M.M.; Covaci, L.; Peeters, F.M. pdf  doi
openurl 
  Title Dynamic and static phases of vortices under an applied drive in a superconducting stripe with an array of weak links Type A1 Journal article
  Year 2012 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume (down) 85 Issue 4 Pages 130-130,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Static and dynamic properties of superconducting vortices in a superconducting stripe with a periodic array of weakly-superconducting (or normal metal) regions are studied in the presence of external magnetic and electric fields. The time-dependent Ginzburg-Landau theory is used to describe the electronic transport, where the anisotropy is included through the spatially-dependent critical temperature T-c. Superconducting vortices penetrating into the weak-superconducting region with smaller T-c are more mobile than the ones in the strong superconducting regions. We observe periodic entrance and exit of vortices which reside in the weak link for some short interval. The mobility of the weakly-pinned vortices can be reduced by increasing the uniform applied magnetic field leading to distinct features in the voltage vs. magnetic field response of the system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000303545400013 Publication Date 2012-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028;1434-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 32 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral programme between Flanders and Brazil. G.R.B. and L.C. acknowledge individual support from FWO-Vl. A.R.de C.R. acknowledges CNPq and FACEPE for financial support. ; Approved Most recent IF: 1.461; 2012 IF: 1.282  
  Call Number UA @ lucian @ c:irua:98267 Serial 761  
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Author Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Effect of nonhomogenous dielectric background on the plasmon modes in graphene double-layer structures at finite temperatures Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 19 Pages 195444-195444,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We have calculated the plasmon modes in graphene double layer structures at finite temperatures, taking into account the inhomogeneity of the dielectric background of the system. The effective dielectric function is obtained from the solution of the Poisson equation of a three-layer dielectric medium with graphene sheets located at the interfaces, separating the different materials. Due to the momentum dispersion of the effective dielectric function, the intra- and interlayer bare Coulomb interactions in the graphene double layer system acquires an additional momentum dependence-an effect that is of the order of the interlayer interaction itself. We show that the energies of the in-phase and out-of-phase plasmon modes are determined largely by different values of the spatially dependent effective dielectric function. The effect of the dielectric inhomogeneity increases with temperature, and even at high temperatures the energy shift induced by the dielectric inhomogeneity and temperature itself remains larger than the broadening of the plasmon energy dispersions due to the Landau damping. The obtained new features of the plasmon dispersions can be observed in frictional drag measurements and in inelastic light scattering and electron energy-loss spectroscopies.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304394800011 Publication Date 2012-05-23  
  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 67 Open Access  
  Notes ; We thank G. Vignale for useful discussions and acknowledge support from the Flemisch Science Foundation (FWO-Fl) and the Belgian Science Policy (BELSPO). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98941 Serial 826  
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Author Shakouri, K.; Szafran, B.; Esmaeilzadeh, M.; Peeters, F.M. url  doi
openurl 
  Title Effective spin-orbit interaction Hamiltonian for quasi-one-dimensional quantum rings Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 16 Pages 165314-165314,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The effective Hamiltonian for an electron in a quasi-one-dimensional quantum ring in the presence of spin-orbit interactions is derived. We demonstrate that, when both coupling types are simultaneously present, the effective Hamiltonian derived by the lowest-radial-state approximation produces energy spectra and charge densities which deviate strongly from the exact ones. For equal Rashba and Dresselhaus coupling constants the lowest-radial-state approximation opens artifactal avoided crossings in the energy spectra and deforms the circular symmetry of the confined charge densities. In this case, there does not exist a ring thin enough to justify the restriction to the lowest radially quantized energy state. We derive the effective Hamiltonian accounting for both the lowest and the first excited radial states, and show that the inclusion of the latter restores the correct features of the exact solution. Relation of this result to the states of a quantum wire is also discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000303068800006 Publication Date 2012-04-20  
  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 32 Open Access  
  Notes ; This work was partially supported by Polish Ministry of Science and Higher Education and its grants for Scientific Research. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98258 Serial 855  
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Author Nasr Esfahani, D.; Covaci, L.; Peeters, F.M. url  doi
openurl 
  Title Electric-field-induced shift of the Mott metal-insulator transition in thin films Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 8 Pages 085110-085110,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The ground-state properties of a paramagnetic Mott insulator at half-filling are investigated in the presence of an external electric field using the inhomogeneous Gutzwiller approximation for a single-band Hubbard model in a slab geometry. We find that the metal-insulator transition is shifted toward higher Hubbard repulsions by applying an electric field perpendicular to the slab. The main reason is the accumulation of charges near the surface. The spatial distribution of site-dependent quasiparticle weight shows that it is maximal in a few layers beneath the surface, while the central sites where the field is screened have a very low quasiparticle weight. Our results show that above a critical-field value, states near the surface will be metallic, while the bulk quasiparticle weight is extremely suppressed but never vanishing, even for large Hubbard repulsions above the bulk zero-field critical value. Below the critical-field value, our results hint toward an insulating state in which the electric field is totally screened and the slab is again at half-filling.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000300240100002 Publication Date 2012-02-14  
  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 3 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:97208 Serial 884  
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Author Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Electron-phonon bound state in graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 20 Pages 205453-205453,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The fine structure of the Dirac energy spectrum in graphene induced by electron-optical phonon coupling is investigated in the portion of the spectrum near the phonon emission threshold. The derived new dispersion equation in the immediate neighborhood below the threshold corresponds to an electron-phonon bound state. We find that the singular vertex corrections beyond perturbation theory strongly increase the electron-phonon binding energy scale. The predicted enhancement of the effective electron-phonon coupling can be measured using angle-resolved spectroscopy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304649400002 Publication Date 2012-05-30  
  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 ; We thank E. Rashba for the useful discussion and acknowledge support from the Belgian Science Policy (IAP) and BELSPO. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98939 Serial 982  
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Author Krstajić, P.M.; Peeters, F.M. url  doi
openurl 
  Title Energy-momentum dispersion relation of plasmarons in graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 20 Pages 205454-205454,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The many-body correction to the band structure of a quasi-free-standing graphene layer is obtained within the Overhauser approach, where the electron-plasmon interaction is described as a field theoretical problem. We find that the Dirac-like spectrum is shifted by Delta E(k = 0), which is on the order of 50-150 meV, depending on the electron concentration n(e), and is in semiquantitative agreement with experimental data. The value of the Fermi velocity is renormalized by several percents and decreases with increasing electron concentration as found experimentally.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304649900004 Publication Date 2012-06-05  
  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 11 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CON-GRAN, and the Serbian Ministry of Education and Science (project No. TR 32008). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98937 Serial 1043  
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Author Vodolazov, D.Y.; Peeters, F.M. url  doi
openurl 
  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 (down) 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.  
  Address  
  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  
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Author Vagov, A.V.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. url  doi
openurl 
  Title Extended Ginzburg-Landau formalism : systematic expansion in small deviation from the critical temperature Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 1 Pages 014502-014502,17  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Based on the Gor'kov formalism for a clean s-wave superconductor, we develop an extended version of the single-band Ginzburg-Landau (GL) theory by means of a systematic expansion in the deviation from the critical temperature T(c), i.e., tau = 1 – T/T(c). We calculate different contributions to the order parameter and the magnetic field: the leading contributions (proportional to tau(1/2) in the order parameter and. t in the magnetic field) are controlled by the standard GL theory, while the next-to-leading terms (proportional to tau(3/2) in the gap and proportional to tau(2) in the magnetic field) constitute the extended GL (EGL) approach. We derive the free-energy functional for the extended formalism and the corresponding expression for the current density. To illustrate the usefulness of our formalism, we calculate, in a semianalytical form, the temperature-dependent correction to the GL parameter at which the surface energy becomes zero, and analytically, the temperature dependence of the thermodynamic critical field. We demonstrate that the EGL formalism is not just a mathematical extension to the theory: variations of both the gap and the thermodynamic critical field with temperature calculated within the EGL theory are found in very good agreement with the full BCS results down to low temperatures, which dramatically improves the applicability of the formalism compared to its standard predecessor.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000298985100002 Publication Date 2012-01-10  
  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 36 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). A. V. V. is grateful to V. Zalipaev for important comments. A. A. S. thanks W. Pogosov for helpful notes. Discussions with E. H. Brandt and A. Perali are appreciated. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:96232 Serial 1155  
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Author Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D. url  doi
openurl 
  Title Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 9 Pages 092502-092502,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000301183000002 Publication Date 2012-03-07  
  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 14 Open Access  
  Notes ; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:97180 Serial 1243  
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Author Saniz, R.; Partoens, B.; Peeters, F.M. url  doi
openurl 
  Title Green function approach to superconductivity in nanowires Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 14 Pages 144504-144504,7  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Superconductivity in nanowires made of weak coupling superconductor materials is investigated using a Green function approach. We show that these are multigap systems in which the ratio Delta(T)/k(B)T(c) is to a large extent similar to what is observed in some high-T-c two-gap systems, such as MgB2 and some of the Fe-based superconductors. On the other hand, because of confinement, the superfluid density has a temperature behavior of the form n(s)(T) = 1 – (T/T-c)(3) near T-c, thus deviating from the BCS behavior for bulk superconductors.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000302290700006 Publication Date 2012-04-03  
  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 1 Open Access  
  Notes ; This work was supported by FWO-Vl and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:97764 Serial 1381  
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Author Čukarić, N.; Arsoski, V.; Tadić, M.; Peeters, F.M. url  doi
openurl 
  Title Hole states in nanocups in a magnetic field Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 23 Pages 235425-235425,11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The magnetic-field dependence of the hole states in a nanocup, which is composed of a ring (the nanocup rim) that surrounds a disk (the nanocup bottom), is obtained within the Luttinger-Kohn model for the unstrained GaAs/(Al,Ga) As and the strained (In,Ga) As/GaAs systems. Aharonov-Bohm oscillations due to angular momentum transitions of the hole ground state appear with periods that vary with the thickness of the disk. The strain in the (In, Ga) As/GaAs nanocup is sensitive to the disk thickness and favors the spatial localization of the heavy holes inside the disk. Therefore, the angular momentum transitions between the valence-band states disappear for much thinner disks than in the case of the unstrained GaAs/(Al, Ga) As nanocups. In both systems, the oscillations in the energy of the hole ground state are found to disappear for thinner inner layer than in the electron ground-state energy. This is due to the different confining potentials and the mixing between the heavy- and light-hole states. As a consequence, magnetization of the single hole is found to strongly depend on the bottom thickness of the strained (In, Ga) As/GaAs nanocup. Furthermore, we found that the strain can lead to a spatial separation of the electron and the hole, as in type-II band alignment, which is advantageous for the appearance of the excitonic Aharonov-Bohm effect.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000305116700005 Publication Date 2012-06-14  
  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 4 Open Access  
  Notes ; The authors thank B. Partoens for useful discussions. This work was supported by the EU NoE: SANDiE, the Ministry of Education and Science of Serbia, and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98906 Serial 1477  
Permanent link to this record
 

 
Author Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. url  doi
openurl 
  Title Magnetotransport in periodically modulated bilayer graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 24 Pages 245426-245426,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Magnetotransport in bilayer graphene in the presence of a weak and periodic potential is investigated in the presence of a perpendicular magnetic field B. The modulation broadens the Landau levels into bands and for weak magnetic fields leads to the well-known Weiss oscillations in their bandwidth and their transport coefficients at very low B and to the Shubnikov-de Haas oscillations at larger B. The amplitude of the Weiss oscillations is severely reduced if the periodic potentials applied to the two layers oscillate out of phase. We also contrast some results with those corresponding to single-layer graphene. Relative to them the flat-band condition and the oscillation amplitude differ substantially, due to the interlayer coupling, and agree only when this coupling is extremely weak. We further show that the Hall conductivity exhibits the well-known steps at half-integer and integer multiples of 4e(2)/h in single-layer and bilayer graphene, respectively, even for very weak magnetic fields. The results are pertinent to weak and periodic corrugations when the potential modulation dominates the strain-induced magnetic modulation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000305253600012 Publication Date 2012-06-14  
  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 supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CON-GRAN), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:99077 Serial 1934  
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Author Clem, J.R.; Mawatari, Y.; Berdiyorov, G.R.; Peeters, F.M. url  doi
openurl 
  Title Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 14 Pages 144511-144511,16  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length xi but much smaller than the Pearl length Lambda = 2 lambda(2)/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 degrees or 180 degrees turns, the zero-field critical current at H = 0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000302611100004 Publication Date 2012-04-10  
  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 40 Open Access  
  Notes ; This research, supported in part by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering, was performed in part at the Ames Laboratory, which is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. This work also was supported in part by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). G.R.B. acknowledges individual support from FWO-Vlaanderen. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98263 Serial 2695  
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Author Krstajić, P.M.; Peeters, F.M. url  doi
openurl 
  Title Remote electron plasmon polaron in graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 8 Pages 085436-085436,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The Coulomb interaction and the correlation of a remote electron with a single layer of graphene is investigated in the presence of a magnetic field applied perpendicular to the graphene layer. The remote electron polarizes the electron gas in the graphene layer, which we describe in terms of excitations of virtual plasmons in graphene. The composite quasiparticle formed by electron plus polarization is called a plasmon polaron. The ground-state energy of this quasiparticle is calculated within perturbation theory for remote electrons in different environments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000300831900012 Publication Date 2012-02-27  
  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 4 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:97202 Serial 2869  
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Author Molnar, B.; Vasilopoulos, P.; Peeters, F.M. doi  openurl
  Title Spin-dependent transmission through a chain of rings : influence of a periodically modulated spin-orbit interaction strength or ring radius Type A1 Journal article
  Year 2004 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume (down) 85 Issue 4 Pages 612-614  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study ballistic electron transport through a finite chain of quantum circular rings in the presence of spin-orbit interaction of strength alpha. For a single ring, the transmission and reflection coefficients are obtained analytically and from them the conductance for a chain of rings as a function of alpha and of the wave vector k of the incident electron. We show that due to destructive spin interferences, the chain can be totally opaque for certain ranges of k, the width of which depends on the value of alpha. A periodic modulation of the strength alpha or of the ring radius widens the gaps considerably and produces a nearly binary conductance output. (C) 2004 American Institute of Physics.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000222855400034 Publication Date 2004-07-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 26 Open Access  
  Notes Approved Most recent IF: 3.411; 2004 IF: 4.308  
  Call Number UA @ lucian @ c:irua:94799 Serial 3085  
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Author Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Strain-engineered graphene through a nanostructured substrate : 1 : deformations Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 19 Pages 195445-195445,11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using atomistic simulations we investigate the morphological properties of graphene deposited on top of a nanostructured substrate. Sinusoidally corrugated surfaces, steps, elongated trenches, one-dimensional and cubic barriers, spherical bubbles, Gaussian bumps, and Gaussian depressions are considered as support structures for graphene. The graphene-substrate interaction is governed by van der Waals forces and the profile of the graphene layer is determined by minimizing the energy using molecular dynamics simulations. Based on the obtained optimum configurations, we found that (i) for graphene placed over sinusoidally corrugated substrates with corrugation wavelengths longer than 2 nm, the graphene sheet follows the substrate pattern while for supported graphene it is always suspended across the peaks of the substrate, (ii) the conformation of graphene to the substrate topography is enhanced when increasing the energy parameter in the van der Waals model, (iii) the adhesion of graphene into the trenches depends on the width of the trench and on the graphene's orientation, i. e., in contrast to a small-width (3 nm) nanoribbon with armchair edges, the one with zigzag edges follows the substrate profile, (iv) atomic-scale graphene follows a Gaussian bump substrate but not the substrate with a Gaussian depression, and (v) the adhesion energy due to van der Waals interaction varies in the range [0.1-0.4] J/m(2).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304394800012 Publication Date 2012-05-23  
  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 62 Open Access  
  Notes ; We thank L. Covaci and S. Costamagna for valuable comments. We acknowledge M. Zarenia, M. R. Masir and D. Nasr for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98942 Serial 3166  
Permanent link to this record
 

 
Author Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Strain-engineered graphene through a nanostructured substrate : 2 : pseudomagnetic fields Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 19 Pages 195446-195446,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The strain-induced pseudomagnetic field in supported graphene deposited on top of a nanostructured substrate is investigated by using atomistic simulations. A step, an elongated trench, a one-dimensional barrier, a spherical bubble, a Gaussian bump, and a Gaussian depression are considered as support structures for graphene. From the obtained optimum configurations we found very strong induced pseudomagnetic fields which can reach up to similar to 1000 T due to the strain-induced deformations in the supported graphene. Different magnetic confinements with controllable geometries are found by tuning the pattern of the substrate. The resulting induced magnetic fields for graphene on top of a step, barrier, and trench are calculated. In contrast to the step and trench the middle part of graphene on top of a barrier has zero pseudomagnetic field. This study provides a theoretical background for designing magnetic structures in graphene by nanostructuring substrates. We found that altering the radial symmetry of the deformation changes the sixfold symmetry of the induced pseudomagnetic field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304394800013 Publication Date 2012-05-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 31 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98943 Serial 3167  
Permanent link to this record
 

 
Author Verberck, B.; Partoens, B.; Peeters, F.M.; Trauzettel, B. url  doi
openurl 
  Title Strain-induced band gaps in bilayer graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 12 Pages 125403-125403,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000301113200005 Publication Date 2012-03-06  
  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 53 Open Access  
  Notes ; The authors would like to acknowledge O. Leenaerts, E. Mariani, K. H. Michel, and J. Schelter for useful discussions. B. V. was financially supported by the Flemish Science Foundation (FWO-Vl). This work was financially supported by the ESF program EuroGraphene under projects CONGRAN and ENTS as well as by the DFG. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:97181 Serial 3168  
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Author Chen, Y.; Shanenko, A.A.; Peeters, F.M. url  doi
openurl 
  Title Superconducting transition temperature of Pb nanofilms : impact of thickness-dependent oscillations of the phonon-mediated electron-electron coupling Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 22 Pages 224517-224517,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract To date, several experimental groups reported measurements of the thickness dependence of T-c of atomically uniform single-crystalline Pb nanofilms. The reported amplitude of the T-c oscillations varies significantly from one experiment to another. Here we propose that the reason for this unresolved issue is an interplay of the quantum-size variations in the single-electron density of states with thickness-dependent oscillations in the phonon-mediated electron-electron coupling. Such oscillations in the coupling depend on the substrate material, the quality of the interface, the protection cover, and other details of the fabrication process, changing from one experiment to another. This explains why the available data do not exhibit one-voice consistency about the amplitude of the T-c oscillations. Our analyses are based on a numerical solution of the Bogoliubov-de Gennes equations for a superconducting slab.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000305251300006 Publication Date 2012-06-14  
  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 24 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:99076 Serial 3368  
Permanent link to this record
 

 
Author Lucena, D.; Tkachenko, D.V.; Nelissen, K.; Misko, V.R.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Transition from single-file to two-dimensional diffusion of interacting particles in a quasi-one-dimensional channel Type A1 Journal article
  Year 2012 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E  
  Volume (down) 85 Issue 3:1 Pages 031147-031147,12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Diffusive properties of a monodisperse system of interacting particles confined to a quasi-one-dimensional channel are studied using molecular dynamics simulations. We calculate numerically the mean-squared displacement (MSD) and investigate the influence of the width of the channel (or the strength of the confinement potential) on diffusion in finite-size channels of different shapes (i.e., straight and circular). The transition from single-file diffusion to the two-dimensional diffusion regime is investigated. This transition [ regarding the calculation of the scaling exponent (alpha) of the MSD <Delta x(2)(t)> proportional to t(alpha)] as a function of the width of the channel is shown to change depending on the channel's confinement profile. In particular, the transition can be either smooth (i.e., for a parabolic confinement potential) or rather sharp (i.e., for a hard-wall potential), as distinct from infinite channels where this transition is abrupt. This result can be explained by qualitatively different distributions of the particle density for the different confinement potentials.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor  
  Language Wos 000302117900003 Publication Date 2012-03-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.366 Times cited 38 Open Access  
  Notes ; This work was supported by CNPq, FUNCAP (Pronex grant), the “Odysseus” program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the collaborative program CNPq-FWO-Vl. ; Approved Most recent IF: 2.366; 2012 IF: 2.313  
  Call Number UA @ lucian @ c:irua:97784 Serial 3699  
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Author Latimer, M.L.; Berdiyorov, G.R.; Xiao, Z.L.; Kwok, W.K.; Peeters, F.M. url  doi
openurl 
  Title Vortex interaction enhanced saturation number and caging effect in a superconducting film with a honeycomb array of nanoscale holes Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 85 Issue 1 Pages 012505-012505,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electrical transport properties of a MoGe thin film with a honeycomb array of nanoscale holes are investigated. The critical current of the system shows nonmatching anomalies as a function of applied magnetic field, enabling us to distinguish between multiquanta vortices trapped in the holes and interstitial vortices located between the holes. The number of vortices trapped in each hole is found to be larger than the saturation number predicted for an isolated hole and shows a nonlinear field dependence, leading to the caging effect as predicted from the Ginzburg-Landau (GL) theory. Our experimental results are supplemented by numerical simulations based on the GL theory.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000299867200001 Publication Date 2012-01-26  
  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 41 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP) (theory) and by the US Department of Energy (DOE) Grant No. DE-FG02-06ER46334 (experiment). G. R. B. acknowledges an individual grant from FWO-Vl. W. K. K. acknowledges support from DOE BES under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM), where the focused-ion-beam milling was performed. M.L.L was a recipient of the NIU/ANL Distinguished Graduate Fellowship. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:96224 Serial 3866  
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Author Wu, X.G.; Peeters, F.M.; Wang, Y.J.; McCombe, B.D. url  doi
openurl 
  Title Blocking of the polaron effect and spin-split cyclotron resonance in a two-dimensional electron gas Type A1 Journal article
  Year 2000 Publication Physical review letters Abbreviated Journal Phys Rev Lett  
  Volume (down) 84 Issue Pages 4934-4937  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000087114400038 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.462 Times cited 15 Open Access  
  Notes Approved Most recent IF: 8.462; 2000 IF: 6.462  
  Call Number UA @ lucian @ c:irua:28517 Serial 245  
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Author Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Chiral states in bilayer graphene : magnetic field dependence and gap opening Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 84 Issue 12 Pages 125451-125451,13  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract At the interface of electrostatic potential kink profiles, one-dimensional chiral states are found in bilayer graphene (BLG). Such structures can be created by applying an asymmetric potential to the upper and the lower layers of BLG. We found the following: (i) due to the strong confinement by the single kink profile, the unidirectional states are only weakly affected by a magnetic field; (ii) increasing the smoothness of the kink potential results in additional bound states, which are topologically different from those chiral states; and (iii) in the presence of a kink-antikink potential, the overlap between the oppositely moving chiral states results in the appearance of crossing and anticrossing points in the energy spectrum. This leads to the opening of tunable minigaps in the spectrum of the unidirectional topological states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000295484300016 Publication Date 2011-09-30  
  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 50 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:92915 Serial 358  
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Author Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M. url  doi
openurl 
  Title Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 84 Issue 6 Pages 064522-064522,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000294226000013 Publication Date 2011-08-25  
  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 56 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:92414 Serial 695  
Permanent link to this record
 

 
Author Grujić, M.; Zarenia, M.; Chaves, A.; Tadić, M.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Electronic and optical properties of a circular graphene quantum dot in a magnetic field : influence of the boundary conditions Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 84 Issue 20 Pages 205441-205441,12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract An analytical approach, using the Dirac-Weyl equation, is implemented to obtain the energy spectrum and optical absorption of a circular graphene quantum dot in the presence of an external magnetic field. Results are obtained for the infinite-massand zigzag boundary conditions. We found that the energy spectrum of a dot with the zigzag boundary condition exhibits a zero-energy band regardless of the value of the magnetic field, while for the infinite-mass boundary condition, the zero-energy states appear only for high magnetic fields. The analytical results are compared to those obtained from the tight-binding model: (i) we show the validity range of the continuum model and (ii) we find that the continuum model with the infinite-mass boundary condition describes rather well its tight-binding analog, which can be partially attributed to the blurring of the mixed edges by the staggered potential.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000297295400011 Publication Date 2011-11-21  
  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 78 Open Access  
  Notes ; This work was supported by the EuroGraphene programme of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP), the bilateral projects between Flanders and Brazil, the Flemish Science Foundation (FWO-Vl), and the Brazilian Research Council (CNPq). ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:94025 Serial 997  
Permanent link to this record
 

 
Author Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Energy levels of triangular and hexagonal graphene quantum dots : a comparative study between the tight-binding and Dirac equation approach Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume (down) 84 Issue 24 Pages 245403-245403,12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The Dirac equation is solved for triangular and hexagonal graphene quantum dots for different boundary conditions in the presence of a perpendicular magnetic field. We analyze the influence of the dot size and its geometry on their energy spectrum. A comparison between the results obtained for graphene dots with zigzag and armchair edges, as well as for infinite-mass boundary condition, is presented and our results show that the type of graphene dot edge and the choice of the appropriate boundary conditions have a very important influence on the energy spectrum. The single-particle energy levels are calculated as a function of an external perpendicular magnetic field that lifts degeneracies. Comparing the energy spectra obtained from the tight-binding approximation to those obtained from the continuum Dirac equation approach, we verify that the behavior of the energies as a function of the dot size or the applied magnetic field are qualitatively similar, but in some cases quantitative differences can exist.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000297767800008 Publication Date 2011-12-07  
  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 145 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE (project CONGRAN), the Bilateral program between Flanders and Brazil, CAPES and the Brazilian Council for Research (CNPq). ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:93961 Serial 1040  
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