toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. pdf  doi
openurl 
  Title Superconducting nanofilms : molecule-like pairing induced by quantum confinement Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 18 Pages 185701-185701,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000303500900018 Publication Date 2012-04-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 26 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:98223 Serial 3357  
Permanent link to this record
 

 
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 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 (up) 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  
Permanent link to this record
 

 
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 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 (up) 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  
Permanent link to this record
 

 
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 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 (up) 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  
Permanent link to this record
 

 
Author Ludu, A.; Milošević, M.V.; Peeters, F.M. pdf  doi
openurl 
  Title Vortex states in axially symmetric superconductors in applied magnetic field Type A1 Journal article
  Year 2012 Publication Sn – 0378-4754 Abbreviated Journal Math Comput Simulat  
  Volume 82 Issue 7 Pages 1258-1270  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We solve analytically the linearized Ginzburg-Landau (GL) equation in the presence of an uniform magnetic field with cylindrical boundary conditions. The solution of the non-linear GL equation is provided as an expansion in the basis of linearized solutions. We present examples of the resulting vortex structure for a solid and perforated superconducting cylinder. (C) 2012 IMACS. Published by Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000303097000009 Publication Date 2012-02-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4754; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.218 Times cited 1 Open Access  
  Notes ; ; Approved Most recent IF: 1.218; 2012 IF: 0.836  
  Call Number UA @ lucian @ c:irua:98300 Serial 3887  
Permanent link to this record
 

 
Author Yang, W.; Misko, V.R.; Nelissen, K.; Kong, M.; Peeters, F.M. doi  openurl
  Title Using self-driven microswimmers for particle separation Type A1 Journal article
  Year 2012 Publication Soft matter Abbreviated Journal Soft Matter  
  Volume 8 Issue 19 Pages 5175-5179  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Microscopic self-propelled swimmers capable of autonomous navigation through complex environments provide appealing opportunities for localization, pick-up and delivery of micro and nanoscopic objects. Inspired by motile cells and bacteria, man-made microswimmers have been fabricated, and their motion in patterned surroundings has been experimentally studied. We propose to use self-driven artificial microswimmers for the separation of binary mixtures of colloids. We revealed different regimes of separation, including one with a velocity inversion. Our findings could be of use for various biological and medical applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000303208700009 Publication Date 2012-03-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1744-683X;1744-6848; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.889 Times cited 45 Open Access  
  Notes ; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-V1) (Belgium), the National Natural Science Foundation of China (No. 11047111), the State Key Program of National Natural Science of China (No. 51135007), the Research Fund for the Doctoral Program of Higher Education of China (No. 20111415120002), and the Major State Basic Research Development Program of China (973) (No. 2009CB724201). ; Approved Most recent IF: 3.889; 2012 IF: 3.909  
  Call Number UA @ lucian @ c:irua:98326 Serial 3826  
Permanent link to this record
 

 
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 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 (up) 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 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 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 (up) 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  
Permanent link to this record
 

 
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 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 (up) 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  
Permanent link to this record
 

 
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 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 (up) 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  
Permanent link to this record
 

 
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 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 (up) 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  
Permanent link to this record
 

 
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 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 (up) 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 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 (up) 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 Komendová, L.; Chen, Y.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M. url  doi
openurl 
  Title Two-band superconductors : hidden criticality deep in the superconducting state Type A1 Journal article
  Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett  
  Volume 108 Issue 20 Pages 207002-207002,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We show that two-band superconductors harbor hidden criticality deep in the superconducting state, stemming from the critical temperature of the weaker band taken as an independent system. For sufficiently small interband coupling gamma the coherence length of the weaker band exhibits a remarkable deviation from the conventional monotonic increase with temperature, namely, a pronounced peak close to the hidden critical point. The magnitude of the peak scales as proportional to gamma(-mu), with the Landau critical exponent mu = 1/3, the same as found for the mean-field critical behavior with respect to the source field in ferromagnets and ferroelectrics. Here reported hidden criticality of multiband superconductors can be experimentally observed by, e.g., imaging of the variations of the vortex core in a broader temperature range. Similar effects are expected for the superconducting multilayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000304064000017 Publication Date 2012-05-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007;1079-7114; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.462 Times cited 75 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). Useful discussions with A. V. Vagov are acknowledged. ; Approved Most recent IF: 8.462; 2012 IF: 7.943  
  Call Number UA @ lucian @ c:irua:98945 Serial 3770  
Permanent link to this record
 

 
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 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 (up) 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 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 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 (up) 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 Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M. pdf  doi
openurl 
  Title Thermomechanical properties of graphene : valence force field model approach Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 17 Pages 175303-175303,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000303499700012 Publication Date 2012-04-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 29 Open Access  
  Notes ; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:99123 Serial 3639  
Permanent link to this record
 

 
Author Barbier, M.; Papp, G.; Peeters, F.M. doi  openurl
  Title Snake states and Klein tunneling in a graphene Hall bar with a pn-junction Type A1 Journal article
  Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 100 Issue 16 Pages 163121-163121,3  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667]  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000303128500064 Publication Date 2012-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 20 Open Access  
  Notes ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ; Approved Most recent IF: 3.411; 2012 IF: 3.794  
  Call Number UA @ lucian @ c:irua:99129 Serial 3047  
Permanent link to this record
 

 
Author Arsoski, V.; Čukarić, N.; Tadić, M.; Peeters, F.M. pdf  doi
openurl 
  Title Exciton states in a nanocup in the presence of a perpendicular magnetic field Type A1 Journal article
  Year 2012 Publication Physica scripta Abbreviated Journal Phys Scripta  
  Volume T149 Issue Pages 014054-014054,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The exciton states in a strained (In,Ga)As/GaAs nanocup are theoretically determined. We explore how the nanocup bottom thickness (t) affects the magnetic field dependence of the exciton energy. Strain distribution is computed by the continuum mechanical model under the approximation of isotropic elasticity. The exciton wave functions are expanded into products of the electron and hole envelope functions. For small t, the exciton ground state has zero orbital momentum and exhibits small oscillations of the second derivative when the magnetic field increases. When t approaches the value of the cup height, however, the exciton levels exhibit angular momentum transitions, whose behavior is similar to that for type-II quantum dots. Small oscillations of the oscillator strength for exciton recombination are found when the magnetic field increases. An increase in thickness of the nanocup bottom has only a small effect on those oscillations for the optically active exciton states, but the exciton ground state becomes dark when the magnetic field increases. Hence, the results of our calculations show that an increase in thickness of the nanocup bottom transforms the exciton ground energy level dependence on magnetic field from the one characteristic of type-I rings to the one characteristic of type-II dots.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Stockholm Editor  
  Language Wos 000303523500055 Publication Date 2012-04-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-8949;1402-4896; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.28 Times cited 2 Open Access  
  Notes ; This work was supported by the EU Network of Excellence SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 1.28; 2012 IF: 1.032  
  Call Number UA @ lucian @ c:irua:99135 Serial 1117  
Permanent link to this record
 

 
Author Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M. pdf  doi
openurl 
  Title Interband optical absorption in a circular graphene quantum dot Type A1 Journal article
  Year 2012 Publication Physica scripta Abbreviated Journal Phys Scripta  
  Volume T149 Issue Pages 014056-014056,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Stockholm Editor  
  Language Wos 000303523500057 Publication Date 2012-04-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-8949;1402-4896; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.28 Times cited 5 Open Access  
  Notes ; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.28; 2012 IF: 1.032  
  Call Number UA @ lucian @ c:irua:99136 Serial 1688  
Permanent link to this record
 

 
Author Dong, H.M.; Xu, W.; Zhang, J.; Peeters, F.M.; Vasilopoulos, P. pdf  doi
openurl 
  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 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 (up) 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 Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. doi  isbn
openurl 
  Title Tuning the superconducting properties of nanomaterials Type H1 Book chapter
  Year 2009 Publication Abbreviated Journal  
  Volume Issue Pages 1-14  
  Keywords H1 Book chapter; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)  
  Abstract Electron continement and its effect on the superconducting-to-normal phase transition driven by a magentic field and/or a current is studied in nanowires. Our investigation is based on a self-consistent numerical solution of the Bogoliubov-de Gennes equations. We find that in a parallel magneitc field and/or in the presence of a supercurrent the transition from the superconducting to the normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magentic field exhibits quantum-size oscillations with pronounced resonant enhancements as a function of the wire radius.  
  Address  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Dordrecht Editor  
  Language Wos 000274282900001 Publication Date 2009-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1874-6500; ISBN 978-90-481-3118-1 Additional Links (up) UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:99226 Serial 3761  
Permanent link to this record
 

 
Author Doria, M.M.; de Romaguera, A.R.C.; Milošević, M.V.; Peeters, F.M. url  doi
openurl 
  Title Domain coexistence of magnetism and superconductivity : appearance of confined vortex loops Type P1 Proceeding
  Year 2008 Publication Journal of physics : conference series Abbreviated Journal  
  Volume 97 Issue Pages 012070-012070,4  
  Keywords P1 Proceeding; Condensed Matter Theory (CMT)  
  Abstract A magnetic moment inside an extreme type II superconductor can have three, but not one or two, confined vortex loops near to the core. For a sub-micron superconducting particle the confined vortex loops eventually break up and reach the surface turning into external vortex pairs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000276054100070 Publication Date 2008-03-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6596; ISBN Additional Links (up) UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:99232 Serial 747  
Permanent link to this record
 

 
Author Baelus, B.J.; Kanda, A.; Peeters, F.M.; Ootuka, Y.; Kadowaki, K. pdf  doi
openurl 
  Title Giant and multivortex states in mesoscopic superconducting disks Type A1 Journal article
  Year 2005 Publication Physica: C : superconductivity Abbreviated Journal Physica C  
  Volume 426 Issue 1 Pages 132-135  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Transitions between different multivortex states and transitions between multivortex states and giant vortex states are observed in mesoscopic superconducting disks using the multiple-small-tunnel-junction method. These results are compared to theoretical calculations within the framework of the nonlinear Ginzburg-Landau theory. We find a good qualitative agreement between the theoretical and experimental results, when we assume that a small defect is present near the center of the experimental sample. (c) 2005 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000232698500029 Publication Date 2005-06-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-4534; ISBN Additional Links (up) UA library record; WoS full record  
  Impact Factor 1.404 Times cited Open Access  
  Notes Approved Most recent IF: 1.404; 2005 IF: 0.948  
  Call Number UA @ lucian @ c:irua:99281 Serial 1336  
Permanent link to this record
 

 
Author Papp, G.; Peeters, F.M. pdf  doi
openurl 
  Title Magneto conductance for tunnelling through double magnetic barriers Type A1 Journal article
  Year 2005 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E  
  Volume 25 Issue 4 Pages 339-346  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The temperature-dependent magnetoresistance effect is investigated in a magnetically modulated two-dimensional (21)) electron gas (2DEG) which can be realized by depositing two parallel ferromagnets on top of a 2DEG electron gas. In the resonant tunnelling regime the transmission for the parallel and antiparallel magnetization configurations shows a quite distinct dependence on the longitudinal wave vector of the incident electrons. This leads to a very large magneto resistance ratio with a strong temperature dependence. (C) 2004 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher North-Holland Place of Publication Amsterdam Editor  
  Language Wos 000226187900002 Publication Date 2004-09-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1386-9477; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.221 Times cited 25 Open Access  
  Notes Approved Most recent IF: 2.221; 2005 IF: 0.946  
  Call Number UA @ lucian @ c:irua:99308 Serial 1898  
Permanent link to this record
 

 
Author Tadić, M.; Peeters, F.M. pdf  doi
openurl 
  Title Exciton states and oscillator strength in two vertically coupled InP/InGaP quantum discs Type A1 Journal article
  Year 2004 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 16 Issue 47 Pages 8633-8652  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Quantum mechanical coupling and strain in two vertically arranged InP/InGaP quantum dots is studied as a function of the size of the dots and the spacer thickness. The strain distribution is determined by the continuum mechanical model, while the single-band effective-mass equation and the multiband k (.) p theory are employed to compute the conduction and valence band energy levels, respectively. The exciton states are obtained from an exact diagonalization approach, and we also compute the oscillator strength for recombination. We found that the light holes are confined by strain to the spacer, which is the reason that the hole states exhibit coupling at much larger distances as compared with the electrons. At small d, the doublet structure of the hole energy levels arises as a consequence of the relocation of the light hole from the matrix to the regions located-outside the stack, close to the dot-matrix interface. When d varies, the exciton ground state exhibits numerous anticrossings with other states, which are related to the changing spatial localization of the hole as a function of d. The oscillator strength of the exciton recombination is strongly reduced in a certain range of spacer thicknesses, which effectively turns a bright exciton state into a dark one. This effect is associated with anticrossings between exciton energy levels.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000225796800016 Publication Date 2004-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 13 Open Access  
  Notes Approved Most recent IF: 2.649; 2004 IF: 2.049  
  Call Number UA @ lucian @ c:irua:99315 Serial 1116  
Permanent link to this record
 

 
Author Anisimovas, E.; Peeters, F.M. url  doi
openurl 
  Title Dynamic response of artificial bipolar molecules Type A1 Journal article
  Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 66 Issue 7 Pages 075311  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We calculate the equilibrium properties and the dynamic response of two vertically coupled circular quantum dots populated by particles of different electrical charge sign, i.e., electrons and holes. The equilibrium density profiles are obtained and used to compute the frequencies and oscillator strengths of magnetoplasma excitations. We find a strong coupling between the modes derived from the center-of-mass modes of the individual dots which leads to an anticrossing with a pronounced oscillator strength transfer from the “acoustic” to the “optical” branch. Also, due to the breaking of the generalized Kohn theorem a number of other than center-of-mass modes are excited whose oscillator strengths, however, are rather weak.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000177969800103 Publication Date 2002-10-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 9 Open Access  
  Notes Approved Most recent IF: 3.836; 2002 IF: NA  
  Call Number UA @ lucian @ c:irua:99397 Serial 765  
Permanent link to this record
 

 
Author Peeters, F.M.; Schweigert, V.A.; Baelus, B.J. doi  openurl
  Title Fractional and negative flux penetration in mesoscopic superconducting disks Type A1 Journal article
  Year 2002 Publication Physica: C : superconductivity Abbreviated Journal Physica C  
  Volume 369 Issue 1-4 Pages 158-164  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The one vortex entry in a superconducting disk is investigated within the non-linear Ginzburg-Landau theory near the first critical field. We find that in mesoscopic superconducting disks the magnetic flux enters with fractions of one flux quantum phi(0) = ch/2e. For disks with a very smooth surface it is possible to drive the Meissner state so far into the metastable region that at the vortex entry a net amount of flux is expelled from the superconductor. We show that the magnetic field for flux entry is very sensitive to indentations of the disk surface and only weakly to bulges. On the other hand the flux exit field is practically insensitive to such geometrical surface defects. Our results are in agreement with recent experimental findings. (C) 2001 Elsevier Science B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000174200000023 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-4534; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.404 Times cited 11 Open Access  
  Notes Approved Most recent IF: 1.404; 2002 IF: 0.912  
  Call Number UA @ lucian @ c:irua:99412 Serial 1272  
Permanent link to this record
 

 
Author Riva, C.; Peeters, F.M.; Varga, K.; Schweigert, V.A. pdf  doi
openurl 
  Title Correlation energy and configuration of biexcitons in quantum wells Type A1 Journal article
  Year 2002 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B  
  Volume 234 Issue 1 Pages 50-57  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A calculation of the energy of a biexciton in a GaAs/AlGaAs quantum wen is presented. We compare the results obtained using two different techniques. We discuss the dependence of the biexciton correlation energy and binding energy on the electron/hole mass ratio and on the well width. The structure of the biexciton is also investigated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000179600900009 Publication Date 2002-11-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972;1521-3951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.674 Times cited 6 Open Access  
  Notes Approved Most recent IF: 1.674; 2002 IF: 0.930  
  Call Number UA @ lucian @ c:irua:99604 Serial 526  
Permanent link to this record
 

 
Author Hilber, W.; Helm, M.; Peeters, F.M.; Alavi, K.; Pathak, R.N. url  doi
openurl 
  Title Impurity band and magnetic-field-induced metal-insulator transition in a doped GaAs/AlxGa1-xAs superlattice Type A1 Journal article
  Year 1996 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 53 Issue 11 Pages 6919-6922  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A combination of infrared spectroscopy and magnetotransport is used to investigate the impurity band and the magnetic-field-induced metal-insulator transition in n-type GaAs/AlxGa1-xAs superlattices. The dropping of the Fermi level from the conduction band into the impurity band upon increasing magnetic field is observed in a sample doped to n=4n(c), where n(c) is the critical density according to the Mott criterion. The metal-insulator transition takes place while the Fermi level is in the impurity band, with no qualitative change from the metallic to the insulating side. Due to the anisotropy of the superlattice band structure, the metal-insulator transition is shifted to higher magnetic field, when the magnetic field is tilted away from the growth axis towards the layer planes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1996UC74000018 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 (up) UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.736 Times cited 14 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:99676 Serial 1571  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: