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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 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 (down) UA @ lucian @ c:irua:104140 Serial 640
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Author Vasilopoulos, P.; Wang, X.F.; Peeters, F.M.; Chowdhury, S.; Long, A.R.; Davies, J.H.
Title Magneto resistance oscillations in a modulated 2DEG periodic in the ratio h/e to flux per unit cell Type A1 Journal article
Year 2004 Publication Physica. E: Low-dimensional systems and nanostructures T2 – 15th International Conference on Electronic Properties of, Two-Dimensional Systems (EP2DS-15), JUL 14-18, 2003, Nara, JAPAN Abbreviated Journal Physica E
Volume 22 Issue 1-3 Pages 389-393
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Transport properties of the 2DEG are studied in the presence of a normal magnetic field B and of a weak, two-dimensional periodic potential modulation. A tight-binding treatment has shown that each Landau level splits into several subbands with exponentially small gaps between them. Assuming the latter are closed due to disorder gives analytical wave functions and simplifies the evaluation of the magnetoresistance tensor p(muv) The relative phase of the oscillations in p(xx) and p(yy) depends on the modulation strengths and periods. For short periods less than or equal to 100 nm, in addition to the Weiss oscillations, the collisional contribution to the conductivity and the corresponding resistivity contribution show prominent peaks when one flux quantum h/e passes through an integral number of unit cells in good agreement with experiments. For periods 300-400 nm long used in early experiments, these peaks occur at fields 10-25 times smaller than those of the Weiss oscillations and are not resolved. (C) 2003 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000221140800094 Publication Date 2004-02-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links UA library record; WoS full record
Impact Factor 2.221 Times cited Open Access
Notes Approved Most recent IF: 2.221; 2004 IF: 0.898
Call Number (down) UA @ lucian @ c:irua:104107 Serial 1911
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Author Pereira, J.M., Jr.; Mlinar, V.; Peeters, F.M.; Vasilopoulos, P.
Title Graphene-based quantum wires Type P1 Proceeding
Year 2007 Publication AIP conference proceedings T2 – 28th International Conference on the Physics of Semiconductors (ICPS-28), JUL 24-28, 2006, Vienna, AUSTRIA Abbreviated Journal
Volume Issue Pages 721-722
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract We investigate the properties of carriers in graphene-based quantum wires created by potential barriers, by means of analytical and numerical calculations. We obtain expressions for the energy spectrum as a function of barrier height, well width and linear momentum along the wire. The results demonstrate a direction-dependent resonant transmission across the potential well.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume 893 Series Issue Edition
ISSN 978-0-7354-0397-0; 0094-243x ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (down) UA @ lucian @ c:irua:103601 Serial 1369
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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 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 (down) UA @ lucian @ c:irua:103199 Serial 1633
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Author Peeters, F.M.; Vasilopoulos, P.
Title Electrical and thermal-properties of a 2-dimensional electron-gas in a one-dimensional periodic potential Type A1 Journal article
Year 1992 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 46 Issue 8 Pages 4667-4680
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the influence of a periodic weak modulation along the x direction on the electrical and thermal properties of a two-dimensional electron gas in the presence of a perpendicular magnetic field. The modulation lifts the degeneracy of the Landau levels and leads to one-dimensional magnetic bands whose bandwidth oscillates as a function of the magnetic field. At weak magnetic fields this gives rise to the Weiss oscillations in the magnetoresistance, discovered recently, which have a very weakly temperature-dependent amplitude and a period proportional to square-root n(e), when n(e) is the electron density. Diffusion-current contributions, proportional to the square of the bandwidth, dominate rho(xx), and collisional contributions, varying approximately as the square of the density of states, dominate rho(yy). The result is that rho(xx) and rho(yy) oscillate out of phase as observed. Asymptotic analytical expressions are presented for the conductivity tensor. Similar oscillations, of much smaller amplitude, occur in the thermodynamic quantities, such as the magnetization, the susceptibility, and the specific heat. We also predict oscillations in the Hall resistance, the cyclotron resonance position, the linewidth, as well as in the thermal conductivity and thermopower. The components of the thermal-resistance tensor have a magnetic-field dependence similar to that of the electrical-resistivity tensor.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1992JK72500032 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 148 Open Access
Notes Approved INSTRUMENTS & INSTRUMENTATION 31/56 Q3 # NUCLEAR SCIENCE & TECHNOLOGY 9/32 Q2 # PHYSICS, PARTICLES & FIELDS 24/28 Q4 # SPECTROSCOPY 28/43 Q3 #
Call Number (down) UA @ lucian @ c:irua:103028 Serial 889
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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 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 (down) UA @ admin @ c:irua:152652 Serial 7878
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Author Tahir, M.; Vasilopoulos, P.; Peeters, F.M.
Title Magneto-optical transport properties of monolayer phosphorene Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 045420
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of monolayer phosphorene are exotic due to its puckered structure and large intrinsic direct band gap. We derive and discuss its band structure in the presence of a perpendicular magnetic field. Further, we evaluate the magneto-optical Hall and longitudinal optical conductivities as functions of temperature, magnetic field, and Fermi energy, and show that they are strongly influenced by the magnetic field. The imaginary part of the former and the real part of the latter exhibit regular interband oscillations as functions of the frequency omega in the range (h) over bar omega similar to 1.5-2 eV. Strong intraband responses in the latter and weak ones in the former occur at much lower frequencies. The magneto-optical response can be tuned in the microwave-to-terahertz and visible frequency ranges in contrast with a conventional two-dimensional electron gas or graphene in which the response is limited to the terahertz regime. This ability to isolate carriers in an anisotropic structure may make phosphorene a promising candidate for new optical devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000358373600003 Publication Date 2015-07-23
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 68 Open Access
Notes ; This work was supported by the the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number (down) c:irua:127192 Serial 1903
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