Home << 1 2 3 >>
List View
 | 
Citations
 | 
Details
   web
Records
Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.; Pereira, J.M.
Title Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue (up) 15 Pages 155402,1-155402,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approximation. For zero bias the dispersion relation shows a finite gap for carriers with zero momentum in the direction parallel to the barriers. This is in contrast to single-layer graphene where no such gap was found. A gap also appears for a finite bias. Numerical results for the energy spectrum, conductance, and the density of states are presented and contrasted with those pertaining to single-layer graphene.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000265944200091 Publication Date 2009-04-01
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 74 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:77025 Serial 235
Permanent link to this record
 
 
Author Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
Title Electrostatically confined trilayer graphene quantum dots Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal
Volume 95 Issue (up) 15 Pages 155434
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Electrically gating of trilayer graphene (TLG) opens a band gap offering the possibility to electrically engineer TLG quantum dots. We study the energy levels of such quantum dots and investigate their dependence on a perpendicular magnetic field B and different types of stacking of the graphene layers. The dots are modeled as circular and confined by a truncated parabolic potential which can be realized by nanostructured gates or position-dependent doping. The energy spectra exhibit the intervalley symmetry E-K(e) (m) = -E (h)(K') (m) for the electron (e) and hole (h) states, where m is the angular momentum quantum number and K and K' label the two valleys. The electron and hole spectra for B = 0 are twofold degenerate due to the intervalley symmetry E-K (m) = E-K' [-(m + 1)]. For both ABC [alpha = 1.5 (1.2) for large (small) R] and ABA (alpha = 1) stackings, the lowest-energy levels show approximately a R-alpha dependence on the dot radius R in contrast with the 1/R-3 one for ABC-stacked dots with infinite-mass boundary. As functions of the field B, the oscillator strengths for dipole-allowed transitions differ drastically for the two types of stackings.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000399797200003 Publication Date 2017-04-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 6 Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:152652 Serial 7878
Permanent link to this record
 
 
Author Wang, X.F.; Vasilopoulos, P.; Peeters, F.M.
Title Spin-current modulation and square-wave transmission through periodically stubbed electron waveguides Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue (up) 16 Pages 165217
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Ballistic spin transport through waveguides, with symmetric or asymmetric double stubs attached to them periodically, is studied systematically in the presence of a weak spin-orbit coupling that makes the electrons precess. By an appropriate choice of the waveguide length and of the stub parameters injected spin-polarized electrons can be blocked completely and the transmission shows a periodic and nearly-square-type behavior, with values 1 and 0, with wide gaps when only one mode is allowed to propagate in the waveguide. A similar behavior is possible for a certain range of the stub parameters even when two modes can propagate in the waveguide and the conductance is doubled. Such a structure is a good candidate for establishing a realistic spin transistor. A further modulation of the spin current can be achieved by inserting defects in a finite-number stub superlattice. Finite-temperature effects on the spin conductance are also considered.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000175325000061 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 112 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:95128 Serial 3082
Permanent link to this record
 
 
Author Borza, S.; Peeters, F.M.; Vasilopoulos, P.; Papp, G.
Title Electric-field manipulation of spin states in confined non-magnetic/magnetic heterostructures Type A1 Journal article
Year 2007 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 19 Issue (up) 17 Pages 176221,1-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000246556400033 Publication Date 2007-04-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 4 Open Access
Notes Approved Most recent IF: 2.649; 2007 IF: 1.886
Call Number UA @ lucian @ c:irua:64758 Serial 885
Permanent link to this record
 
 
Author Pereira, J.M.; Peeters, F.M.; Vasilopoulos, P.; Costa Filho, R.N.; Farias, G.A.
Title Landau levels in graphene bilayer quantum dots Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue (up) 19 Pages 195403,1-195403,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate localized electron and hole states in parabolic quantum dots of biased graphene bilayers in the presence of a perpendicular magnetic field. These quantum dots can be created by means of nanostructured gates or by position-dependent doping, which can create a gap in the otherwise gapless dispersion of a graphene bilayer. Numerical results show the energy levels of confined electrons and holes as a function of the dot parameters and the magnetic field. Remarkable crossings of energy levels are found.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000266501300102 Publication Date 2009-05-05
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 29 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:77401 Serial 1774
Permanent link to this record
 
 
Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
Title Single-layer and bilayer graphene superlattices: collimation, additional Dirac points and Dirac lines Type A1 Journal article
Year 2010 Publication Philosophical transactions of the Royal Society : mathematical, physical and engineering sciences Abbreviated Journal Philos T R Soc A
Volume 368 Issue (up) 1932 Pages 5499-5524
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We review the energy spectrum and transport properties of several types of one-dimensional superlattices (SLs) on single-layer and bilayer graphene. In single-layer graphene, for certain SL parameters an electron beam incident on an SL is highly collimated. On the other hand, there are extra Dirac points generated for other SL parameters. Using rectangular barriers allows us to find analytical expressions for the location of new Dirac points in the spectrum and for the renormalization of the electron velocities. The influence of these extra Dirac points on the conductivity is investigated. In the limit of δ-function barriers, the transmission T through and conductance G of a finite number of barriers as well as the energy spectra of SLs are periodic functions of the dimensionless strength P of the barriers, Graphic, with vF the Fermi velocity. For a KronigPenney SL with alternating sign of the height of the barriers, the Dirac point becomes a Dirac line for P = π/2+nπ with n an integer. In bilayer graphene, with an appropriate bias applied to the barriers and wells, we show that several new types of SLs are produced and two of them are similar to type I and type II semiconductor SLs. Similar to single-layer graphene SLs, extra Dirac points are found in bilayer graphene SLs. Non-ballistic transport is also considered.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000283660000011 Publication Date 2010-11-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1364-503X;1471-2962; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.97 Times cited 64 Open Access
Notes ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Canadian NSERC through grant no. OGP0121756. ; Approved Most recent IF: 2.97; 2010 IF: 2.459
Call Number UA @ lucian @ c:irua:85597 Serial 3023
Permanent link to this record
 
 
Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
Title Dirac electrons in a Kronig-Penney potential: dispersion relation and transmission periodic in the strength of the barriers Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 80 Issue (up) 20 Pages 205415,1-205415,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The transmission T and conductance G through one or multiple one-dimensional, ä-function barriers of two-dimensional fermions with a linear energy spectrum are studied. T and G are periodic functions of the strength P of the ä-function barrier V(x,y)/ℏvF=Pä(x). The dispersion relation of a Kronig-Penney (KP) model of a superlattice is also a periodic function of P and causes collimation of an incident electron beam for P=2ðn and n integer. For a KP superlattice with alternating sign of the height of the barriers the Dirac point becomes a Dirac line for P=(n+1/2)ð.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000272311400101 Publication Date 2009-12-04
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 93 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:80316 Serial 707
Permanent link to this record
 
 
Author Li, L.L.; Moldovan, D.; Vasilopoulos, P.; Peeters, F.M.
Title Aharonov-Bohm oscillations in phosphorene quantum rings Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue (up) 20 Pages 205426
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The Aharonov-Bohm (AB) effect in square phosphorene quantum rings, with armchair and zigzag edges, is investigated using the tight-binding method. The energy spectra and wave functions of such rings, obtained as a function of the magnetic flux Phi threading the ring, are strongly influenced by the ringwidthW, an in-plane electric field E-p, and a side-gating potential V-g. Compared to a square dot, the ring shows an enhanced confinement due to its inner edges and an interedge coupling along the zigzag direction, both of which strongly affect the energy spectrum and the wave functions. The energy spectrum that is gapped consists of a regular part, of conduction (valence) band states, that shows the usual AB oscillations in the higher-(lower-) energy region, and of edge states, in the gap, that exhibit no AB oscillations. As the width W decreases, the AB oscillations become more distinct and regular and their period is close to Phi(0)/2, where the flux quantum Phi(0) = h/e is the period of an ideal circular ring (W -> 0). Both the electric field E-p and the side-gating potential V-g reduce the amplitude of the AB oscillations. The amplitude can be effectively tuned by E-p or V-g and exhibits an anisotropic behavior for different field directions or side-gating configurations.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000402003700010 Publication Date 2017-05-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 16 Open Access
Notes ; This work was financially supported by the Chinese Academy of Sciences, the Flemish Science Foundation (FWO-V1), and by the Canadian NSERC Grant No. OGP0121756 (P.V.). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:144267 Serial 4638
Permanent link to this record
 
 
Author Shakouri, K.; Vasilopoulos, P.; Vargiamidis, V.; Hai, G.-Q.; Peeters, F.M.
Title Spin- and valley-dependent commensurability oscillations and electric-field-induced quantum Hall plateaux in periodically modulated silicene Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 104 Issue (up) 21 Pages 213109
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the commensurability oscillations in silicene subject to a perpendicular electric field E-z, a weak magnetic field B, and a weak periodic potential V = V-0 cos(Cy); C = 2 pi/a(0) with a(0) its period. The field E-z and/or the modulation lift the spin degeneracy of the Landau levels and lead to spin and valley resolved Weiss oscillations. The spin resolution is maximal when the field E-z is replaced by a periodic one E-z = E-0 cos(Dy); D = 2 pi/b(0), while the valley one is maximal for b(0) = a(0). In certain ranges of B values, the current is fully spin or valley polarized. Additional quantum Hall conductivity plateaux arise due to spin and valley intra-Landau-level transitions. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000337143000047 Publication Date 2014-05-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 16 Open Access
Notes ; The work was supported by the Flemish Science Foundation (FWO-VI), the Methusalem Foundation of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756. Also, G. Q. H. was supported by FAPESP and CNPq (Brazil). ; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:118409 Serial 3078
Permanent link to this record
 
 
Author Masir, M.R.; Vasilopoulos, P.; Matulis, A.; Peeters, F.M.
Title Direction-dependent tunneling through nanostructured magnetic barriers in graphene Type A1 Journal article
Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 77 Issue (up) 23 Pages 235443,1-11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000257289500133 Publication Date 2008-06-27
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 212 Open Access
Notes Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number UA @ lucian @ c:irua:69639 Serial 727
Permanent link to this record
 
 
Author Shakouri, K.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.
Title Integer and half-integer quantum Hall effect in silicene: Influence of an external electric field and impurities Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 90 Issue (up) 23 Pages 235423
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The influence of silicene's strong spin-orbit interaction and of an external electric field E-z on the transport coefficients are investigated in the presence of a perpendicular magnetic field B. For finite E-z the spin and valley degeneracy of the Landau levels is lifted and leads to additional plateaus in the Hall conductivity, at half-integer values of 4e(2)/h, due to spin intra-Landau-level transitions that are absent in graphene. These plateaus are more sensitive to disorder and thermal broadening than the main plateaus, occurring at integral values of 4e(2)/h, when the Fermi level passes through the Landau levels. We also evaluate the Hall and longitudinal resistivities and critically contrast the results with those for graphene on a substrate.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346377400004 Publication Date 2014-12-15
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 ; Our work was supported by the Flemish Science Foundation (FWO-VI), the Methusalem Foundation of the Flemish Government, and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:122771 Serial 1678
Permanent link to this record
 
 
Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
Title Kronig-Penney model on bilayer graphene : spectrum and transmission periodic in the strength of the barriers Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 82 Issue (up) 23 Pages 235408-235408,10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We show that the transmission through single and double δ-function potential barriers of strength P=VWb/ℏvF in bilayer graphene is periodic in P with period π. For a certain range of P values we find states that are bound to the potential barrier and that run along the potential barrier. Similar periodic behavior is found for the conductance. The spectrum of a periodic succession of δ-function barriers (Kronig-Penney model) in bilayer graphene is periodic in P with period 2π. For P smaller than a critical value Pc, the spectrum exhibits two Dirac points while for P larger than Pc an energy gap opens. These results are extended to the case of a superlattice of δ-function barriers with P alternating in sign between successive barriers; the corresponding spectrum is periodic in P with period π.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000286766900008 Publication Date 2010-12-06
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 34 Open Access
Notes ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the Canadian NSERC under Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:88910 Serial 1768
Permanent link to this record
 
 
Author Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
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 85 Issue (up) 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
Permanent link to this record
 
 
Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
Title Wavevector filtering through single-layer and bilayer graphene with magnetic barrier structures Type A1 Journal article
Year 2008 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 93 Issue (up) 24 Pages 242103,1-242103,3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We show that the angular range of the transmission through magnetic barrier structures can be efficiently controlled in single-layer and bilayer graphenes and this renders the structures efficient wavevector filters. As the number of magnetic barriers increases, this range shrinks, the gaps in the transmission versus energy become wider, and the conductance oscillates with the Fermi energy.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000261896400032 Publication Date 2008-12-15
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 91 Open Access
Notes Approved Most recent IF: 3.411; 2008 IF: 3.726
Call Number UA @ lucian @ c:irua:75931 Serial 3910
Permanent link to this record
 
 
Author Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
Title Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue (up) 24 Pages 245410
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < |km + 1/2|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > |km + 1/2|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000403072400005 Publication Date 2017-06-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 13 Open Access
Notes ; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:144197 Serial 4661
Permanent link to this record
 
 
Author Wang, X.F.; Vasilopoulos, P.; Peeters, F.M.
Title Influence of spin-orbit interaction on the magnetotransport of a periodically modulated two-dimensional electron gas Type A1 Journal article
Year 2004 Publication International journal of modern physics: B: condensed matter physics, statistical physics, applied physics T2 – 16th International Conference on High Magnetic Fields in Semiconductor, Physics, AUG 02-06, 2004, Florida State Univ, NHMFL, Tallahassee, FL Abbreviated Journal Int J Mod Phys B
Volume 18 Issue (up) 27-29 Pages 3653-3656
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Transport properties of a two-dimensional electron gas (2DEG) are studied in the presence of a normal magnetic field B, of a weak one-dimensional (1D) periodic potential modulation V(x) = V(0)cos(Kx), and of the Rashba spin-orbit interaction (SOI) of strength a. For V(x) = 0 the SOI mixes the up and down spin states of neighboring Landau levels into two, unequally spaced energy branches. For V(x) not equal 0 these levels broaden into bands and their bandwidths oscillate with B. The n-th level bandwidth of each series vanishes at different values of B. Relative to the ID-modulated 2DEG without SOI and one flat-band condition, there are two flat-band conditions that depend on a and the transport coefficients can change considerably. For weak a the Weiss oscillations show beating patterns while for strong a the Shubnikov-de Haas ones axe split in two.
Address
Corporate Author Thesis
Publisher Place of Publication Singapore Editor
Language Wos 000227140200040 Publication Date 2005-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-9792;1793-6578; ISBN Additional Links UA library record; WoS full record
Impact Factor 0.736 Times cited Open Access
Notes Approved Most recent IF: 0.736; 2004 IF: 0.361
Call Number UA @ lucian @ c:irua:103199 Serial 1633
Permanent link to this record
 
 
Author Vasilopoulos, P.; Molnar, B.; Peeters, F.M.
Title Magnetoconductance through a chain of rings in the presence of spin-orbit interaction Type A1 Journal article
Year 2004 Publication International journal of modern physics: B: condensed matter physics, statistical physics, applied physics Abbreviated Journal Int J Mod Phys B
Volume 18 Issue (up) 27-29 Pages 3661-3664
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Ballistic electron transport through a finite chain of quantum circular rings is studied in the presence of the Rashba coupling, of strength a, and of a perpendicular magnetic field B. The transmission and reflection coefficients for a single ring, obtained analytically, help obtain the conductance through a chain of rings as a function of the strength a, the field B, and of the wave vector k of the incident electron. Due to destructive spin interferences caused by the Rashba coupling the chain can be totally opaque for certain ranges of k the width of which depends on values of a and B. Outside these ranges the conductance oscillates with high values between e(2)/h and 2e(2)/h. The effect of a periodic modulation of a or B on the conductance gaps is investigated. A periodic, square-wave conductance pattern, pertinent to the development of the spin transistor, results within wide stripes in the parameter space spanned by k, a, and B. Finite temperatures smoothen the square-wave profile of the conductance but do not alter its periodic character.
Address
Corporate Author Thesis
Publisher Place of Publication Singapore Editor
Language Wos 000227140200042 Publication Date 2005-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-9792;1793-6578; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.736 Times cited 2 Open Access
Notes Approved Most recent IF: 0.736; 2004 IF: 0.361
Call Number UA @ lucian @ c:irua:94787 Serial 1914
Permanent link to this record
 
 
Author Vasilopoulos, P.; Kálmán, O.; Peeters, F.M.; Benedict, M.G.
Title Aharonov-Bohm oscillations in a mesoscopic ring with asymmetric arm-dependent injection Type A1 Journal article
Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 75 Issue (up) 3 Pages 035304,1-7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000243895400086 Publication Date 2007-01-05
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 29 Open Access
Notes Approved Most recent IF: 3.836; 2007 IF: 3.172
Call Number UA @ lucian @ c:irua:63751 Serial 86
Permanent link to this record
 
 
Author Peeters, F.M.; Vasilopoulos, P.
Title Quantum transport of a two-dimensional electron gas in a spatially modulated magnetic field Type A1 Journal article
Year 1993 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 47 Issue (up) 3 Pages 1466-1473
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Electrical transport properties of a two-dimensional electron gas axe studied in the presence of a perpendicular magnetic field B modulated weakly and periodically along one direction, B = (B + B0 cos Kx)z, with B0 much less than B, K = 2pi/a, and a being the period of the modulation. B0 is taken constant or proportional to B. The Landau levels broaden into bands and their width, proportional to the modulation strength B0, oscillates with B and gives rise to oscillations in the magnetoresistance at low B. These oscillations reflect the commensurability between the cyclotron diameter at the Fermi level and the period a and consequently hey are distinctly different from the Shubnikov-de Ha.as ones, at higher B, in period and temperature dependence. The bandwidth at the Fermi energy can be one order of magnitude larger, at low B, than that of the electric case for equal modulation strengths. The resulting magnetoresistance oscillations have a much higher amplitude than those of the electric case with which they are out of phase. Explicit asymptotic expressions are derived for the temperature dependence of the transport coefficients. The case when both electric and magnetic modulations are present is also considered. The position of the resulting oscillations depends on the ratio delta between the two modulation strengths. When the modulations are out of phase there is no shift in the position of the oscillations when delta varies and for a particular value of delta the oscillations are suppressed.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1993KJ51800042 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 169 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:5787 Serial 2795
Permanent link to this record
 
 
Author Van Duppen, B.; Vasilopoulos, P.; Peeters, F.M.
Title Spin and valley polarization of plasmons in silicene due to external fields Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 90 Issue (up) 3 Pages 035142
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of the two-dimensional material silicene are strongly influenced by the application of a perpendicular electric field E-z and of an exchange field M due to adatoms positioned on the surface or a ferromagnetic substrate. Within the random phase approximation, we investigate how electron-electron interactions are affected by these fields and present analytical and numerical results for the dispersion of plasmons, their lifetime, and their oscillator strength. We find that the combination of the fields E-z and M brings a spin and valley texture to the particle-hole excitation spectrum and allows the formation of spin-and valley-polarized plasmons. When the Fermi level lies in the gap of one spin in one valley, the intraband region of the corresponding spectrum disappears. For zero E-z and finite M the spin symmetry is broken and spin polarization is possible. The lifetime and oscillator strength of the plasmons are shown to depend strongly on the number of spin and valley type electrons that form the electron-hole pairs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000339974700001 Publication Date 2014-07-30
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 49 Open Access
Notes ; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) by an aspirant grant to B.V.D., the Methusalem Foundation of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:118776 Serial 3080
Permanent link to this record
 
 
Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
Title Tunneling, conductance, and wavevector filtering through magnetic barriers in bilayer graphene Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue (up) 3 Pages 035409,1-035409,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We evaluate the transmission and conductance through magnetic barrier structures in bilayer graphene. In particular we consider a magnetic step, single and double barriers, -function barriers, as well as barrier structures that have average magnetic field equal to zero. The transmission depends strongly on the direction of the incident electron or hole wavevector and gives the possibility to construct a direction-dependent wavevector filter. The results contrast sharply with previous results on single-layer graphene. In general, the angular range of perfect transmission becomes drastically wider and the gaps narrower. This perfect transmission range decreases with the number of barriers, the barrier width, and the magnetic field. Depending on the structure, a variety of transmission resonances occur that are reflected in the conductance through the structure.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000262978200107 Publication Date 2009-01-14
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 80 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:75983 Serial 3762
Permanent link to this record
 
 
Author Milton Pereira, J.; Vasilopoulos, P.; Peeters, F.M.
Title Resonant tunneling in graphene microstructures Type A1 Journal article
Year 2008 Publication Microelectronics journal Abbreviated Journal Microelectron J
Volume 39 Issue (up) 3-4 Pages 534-536
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Luton Editor
Language Wos 000255600600055 Publication Date 2007-08-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-2692; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.163 Times cited 9 Open Access
Notes Approved Most recent IF: 1.163; 2008 IF: 0.859
Call Number UA @ lucian @ c:irua:68850 Serial 2892
Permanent link to this record
 
 
Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
Title Graphene in inhomogeneous magnetic fields : bound, quasi-bound and scattering states Type A1 Journal article
Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 23 Issue (up) 31 Pages 315301,1-315301,14
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000293008900002 Publication Date 2011-07-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 38 Open Access
Notes ; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE, the Canadian NSERC grant no. OGP0121756 and the Belgian Science Policy (IAP). We acknowledge discussions and correspondence with Professor A Matulis. ; Approved Most recent IF: 2.649; 2011 IF: 2.546
Call Number UA @ lucian @ c:irua:91176 Serial 1372
Permanent link to this record
 
 
Author Peeters, F.M.; Vasilopoulos, P.; Shi, J.
Title Density of states and Fermi level of a periodically modulated two-dimensional electron gas Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue (up) 38 Pages 8803-8816
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Explicit analytic expressions are obtained for the density of states D(E) and Fermi energy E-F of a two-dimensional electron gas in the presence of a weak and periodic unidirectional electric or magnetic modulation and of a uniform perpendicular magnetic field B. The Landau levels broaden into bands and their width, proportional to the modulation strength, oscillates with B and gives rise to Weiss oscillations in D(E), E-F and the transport coefficients. When both electric and magnetic modulations are present the position of the resulting oscillations depends on the ratio delta between the two modulation strengths. When the modulations are out of phase there is no shift in the position of the oscillations when delta varies and for a particular value of delta the oscillations are suppressed.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000178678400008 Publication Date 2002-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 8 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number UA @ lucian @ c:irua:104140 Serial 640
Permanent link to this record
 
 
Author Milton Pereira, J.; Mlinar, V.; Peeters, F.M.; Vasilopoulos, P.
Title Confined states and direction-dependent transmission in graphene quantum wells Type A1 Journal article
Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 74 Issue (up) 4 Pages 045424,1-5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000239426800116 Publication Date 2006-07-25
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 212 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ c:irua:60091 Serial 484
Permanent link to this record
 
 
Author Dong, H.M.; Xu, W.; Zhang, J.; Peeters, F.M.; Vasilopoulos, P.
Title Photo-excited carriers and optical conductance and transmission in graphene in the presence of phonon scattering Type A1 Journal article
Year 2010 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume 42 Issue (up) 4 Pages 748-750
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We present a theoretical study of the optoelectronic properties of monolayer graphene. Including the effect of the electron-photon-phonon scattering, we employ the mass- and energy-balance equations derived from the Boltzmann equation to evaluate self-consistently the carrier densities, optical conductance and transmission coefficient in graphene in the presence of linearly polarized radiation field. We find that the photo-excited carrier density can be increased under infrared radiation and depend strongly on radiation intensity and frequency. For short wavelengths (lambda <3 mu m), the universal optical conductance sigma(0) = e(2)/4h is obtained and the light transmittance is about 0.97-0.98. Interestingly, there is an optical absorption window in the range 4-100 mu m which is induced by different transition energies required for inter- and intra-band optical absorption. The position and width of this absorption window depend sensitively on temperature and carrier density of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000276541200022 Publication Date 2009-11-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 7 Open Access
Notes ; ; Approved Most recent IF: 2.221; 2010 IF: 1.304
Call Number UA @ lucian @ c:irua:99216 Serial 2607
Permanent link to this record
 
 
Author Molnar, B.; Vasilopoulos, P.; Peeters, F.M.
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 85 Issue (up) 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
Permanent link to this record
 
 
Author Milton Pereira, J.; Vasilopoulos, P.; Peeters, F.M.
Title Tunable quantum dots in bilayer graphene Type A1 Journal article
Year 2007 Publication Nano letters Abbreviated Journal Nano Lett
Volume 7 Issue (up) 4 Pages 946-949
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos 000245600500017 Publication Date 2007-03-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 167 Open Access
Notes Approved Most recent IF: 12.712; 2007 IF: 9.627
Call Number UA @ lucian @ c:irua:64118 Serial 3745
Permanent link to this record
 
 
Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
Title Kronig-Penney model of scalar and vector potentials in graphene Type A1 Journal article
Year 2010 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 22 Issue (up) 46 Pages 465302,1-465302,10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We consider a one-dimensional (1D) superlattice (SL) on graphene consisting of very high and very thin (δ-function) magnetic and potential barriers with zero average potential and zero magnetic field. We calculate the energy spectrum analytically, study it in different limiting cases, and determine the condition under which an electron beam incident on an SL is highly collimated along its direction. In the absence of the magnetic SL the collimation is very sensitive to the value of W/Ws and is optimal for W/Ws = 1, where W is the distance between the positive and negative barriers and L = W + Ws is the size of the unit cell. In the presence of only the magnetic SL the collimation decreases and the symmetry of the spectrum around ky is broken for W/Ws\neq 1 . In addition, a gap opens which depends on the strength of the magnetic field. We also investigate the effect of spatially separated potential and magnetic δ-function barriers and predict a better collimation in specific cases.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000283838800004 Publication Date 2010-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 41 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 2.649; 2010 IF: 2.332
Call Number UA @ lucian @ c:irua:85807 Serial 1767
Permanent link to this record
 
 
Author Reijniers, J.; Matulis, A.; Chang, K.; Peeters, F.M.; Vasilopoulos, P.
Title Confined magnetic guiding orbit states Type A1 Journal article
Year 2002 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
Volume 59 Issue (up) 5 Pages 749-753
Keywords A1 Journal article; Engineering Management (ENM); Condensed Matter Theory (CMT)
Abstract We show how snake-orbit states which run along a magnetic edge can be confined electrically. We consider a two-dimensional electron gas (2DEG) confined into a quantum wire, subjected to a strong perpendicular and steplike magnetic field B/ − B. Close to this magnetic step, new, spatially confined bound states arise as a result of the lateral confinement and the magnetic-field step. The number of states, with energy below the first Landau level, increases as B becomes stronger or as the wire width becomes larger. These bound states can be understood as an interference between two counter-propagating one-dimensional snake-orbit states.
Address
Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos 000177761700018 Publication Date 2003-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0295-5075;1286-4854; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.957 Times cited 26 Open Access
Notes Approved Most recent IF: 1.957; 2002 IF: 2.360
Call Number UA @ lucian @ c:irua:92387 Serial 483
Permanent link to this record