|   | 
Details
   web
Records
Author de Oliveira, E.L.; Albuquerque, E.L.; de Sousa, J.S.; Farias, G.A.; Peeters, F.M.
Title Configuration-interaction excitonic absorption in small Si/Ge and Ge/Si core/shell nanocrystals Type A1 Journal article
Year 2012 Publication (down) The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 116 Issue 7 Pages 4399-4407
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals (NC's) with diameters of similar to 1.9 nm are investigated using a combination density functional ab initio method to obtain the single particle wave functions and a configuration interaction method to compute the exciton fine structure and absorption coefficient. These core/shell structures exhibit type II confinement, which is more pronounced for the Si/Ge NC as a consequence of strain. The absorption coefficients of these NC's exhibit a single dominant peak, which has a much larger oscillator strength than the multipeaks found for pure Si and Ge NC's. The exciton lifetime in Si, Ge, and Ge/Si shows a small i:emperature dependence in the range 10-300 K, whereas in Si/Ge, the exciton lifetime decreases more than an order of magnitude in the same temperature range.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000301156500007 Publication Date 2012-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 44 Open Access
Notes ; The authors acknowledge financial support from CNPq and the bilateral program between Flanders and Brazil and the Belgian Science Foundation (IAP). ; Approved Most recent IF: 4.536; 2012 IF: 4.814
Call Number UA @ lucian @ c:irua:113045 Serial 482
Permanent link to this record
 

 
Author Ferreira, W.P.; Farias, G.A.; Carmona, H.A.; Peeters, F.M.
Title Structural transitions in a classical two-dimensional molecule system Type A1 Journal article
Year 2002 Publication (down) Solid state communications Abbreviated Journal Solid State Commun
Volume 122 Issue 12 Pages 665-669
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The ground state of a classical two-dimensional (2D) system with a finite number of charge particles, trapped by two positive impurity charges localized at a distance (z(0)) from the. 2D plane and separated from each other by a distance chi(p) are obtained. The impurities are allowed to carry more than one positive charge. This classical system can form a 2D-like classical molecule that exhibits structural transitions and spontaneous symmetry breaking as function of the separation between the positive charges before it transforms into two 2D-like classical atoms. We also observe structural transitions as a function of the dielectric constant of the substrate which supports the charged particles, in addition to broken symmetry states and unbinding of particles. (C) 2002 Elsevier Science Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000177129500008 Publication Date 2002-10-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 3 Open Access
Notes Approved Most recent IF: 1.554; 2002 IF: 1.671
Call Number UA @ lucian @ c:irua:95137 Serial 3268
Permanent link to this record
 

 
Author Farias, G.A.; Peeters, F.M.
Title Structural transitions in a finite classical two-dimensional system Type A1 Journal article
Year 1996 Publication (down) Solid state communications Abbreviated Journal Solid State Commun
Volume 100 Issue Pages 711-715
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos A1996VU47000008 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.897 Times cited 25 Open Access
Notes Approved
Call Number UA @ lucian @ c:irua:15788 Serial 3269
Permanent link to this record
 

 
Author Pereira, J.M.; Peeters, F.M.; Chaves, A.; Farias, G.A.
Title Klein tunneling in single and multiple barriers in graphene Type A1 Journal article
Year 2010 Publication (down) Semiconductor science and technology Abbreviated Journal Semicond Sci Tech
Volume 25 Issue 3 Pages 033002,1-033002,9
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We review the transmission properties of carriers interacting with potential barriers in graphene. The tunneling of electrons and holes in quantum structures in graphene is found to display features that are in marked contrast with those of other systems. In particular, the interaction between the carriers with electrostatic potential barriers can be related to the propagation of electromagnetic waves in media with negative refraction indices, also known as metamaterials. This behavior becomes evident as one calculates the time evolution of wavepackets propagating across the barrier interface. In addition, we discuss the effect of trigonal warping on the tunneling through potential barriers.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000274318300004 Publication Date 2010-02-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0268-1242;1361-6641; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.305 Times cited 83 Open Access
Notes ; We want to acknowledge our collaborators in this work: P Vasilopoulos and M Barbier. This work was supported by the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 2.305; 2010 IF: 1.333
Call Number UA @ lucian @ c:irua:80961 Serial 1764
Permanent link to this record
 

 
Author de Araujo, J.L.B.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.; Ferreira, W.P.
Title Structure and reentrant percolation in an inverse patchy colloidal system Type A1 Journal article
Year 2017 Publication (down) Physical Review E Abbreviated Journal
Volume 95 Issue 6 Pages 062606
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Two-dimensional systems of inverse patchy colloids modeled as disks with a central charge and having their surface decorated with oppositely pointlike charged patches are investigated using molecular dynamics simulations. The self-assembly of the patchy colloids leads to diverse ground state configurations ranging from crystalline arrangements of monomers to linear clusters, ramified linear clusters and to percolated configurations. Two structural phase diagrams are constructed: (1) as a function of the net charge and area fraction, and (2) as a function of the net charge and the range of the pair interaction potential. An interesting reentrant percolation transition is obtained as a function of the net charge of the colloids. We identify distinct mechanisms that lead to the percolation transition.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000404545700005 Publication Date 2017-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:152628 Serial 8587
Permanent link to this record
 

 
Author da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M.
Title Magnetic field dependence of energy levels in biased bilayer graphene quantum dots Type A1 Journal article
Year 2016 Publication (down) Physical review B Abbreviated Journal Phys Rev B
Volume 93 Issue 93 Pages 085401
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the tight-binding approach, we study the influence of a perpendicular magnetic field on the energy levels of hexagonal, triangular, and circular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We obtain the energy levels for AB (Bernal)-stacked BLG QDs in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). We find different regions in the spectrum of biased QDs with respect to the crossing point between the lowest-electron and -hole Landau levels of a biased BLG sheet. Those different regions correspond to electron states that are localized at the center, edge, or corner of the BLG QD. Quantum Hall corner states are found to be absent in circular BLG QDs. The spatial symmetry of the carrier density distribution is related to the symmetry of the confinement potential, the position of zigzag edges, and the presence or absence of interlayer inversion symmetry.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000369402400008 Publication Date 2016-02-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 22 Open Access
Notes ; This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the Process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836
Call Number c:irua:131623 Serial 4038
Permanent link to this record
 

 
Author da Costa; Zarenia, M.; Chaves, A.; Pereira, J.M., Jr.; Farias, G.A.; Peeters, F.M.
Title Hexagonal-shaped monolayer-bilayer quantum disks in graphene : a tight-binding approach Type A1 Journal article
Year 2016 Publication (down) Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 94 Pages 035415
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the tight-binding approach, we investigate confined states in two different hybrid monolayer-bilayer systems: (i) a hexagonal monolayer area surrounded by bilayer graphene in the presence of a perpendicularly applied electric field and (ii) a hexagonal bilayer graphene dot surrounded by monolayer graphene. The dependence of the energy levels on dot size and external magnetic field is calculated. We find that the energy spectrum for quantum dots with zigzag edges consists of states inside the gap which range from dot-localized states, edge states, to mixed states coexisting together, whereas for dots with armchair edges, only dot-localized states are observed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000379502200008 Publication Date 2016-07-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9950;2469-9969; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes ; This work was financially supported by CNPq, under contract NanoBioEstruturas No. 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation, under the process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, the Brazilian Program Science Without Borders (CsF), and the Lemann Foundation. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:134947 Serial 4190
Permanent link to this record
 

 
Author de Sousa, G.O.; da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M.
Title Unusual quantum confined Stark effect and Aharonov-Bohm oscillations in semiconductor quantum rings with anisotropic effective masses Type A1 Journal article
Year 2017 Publication (down) Physical review B Abbreviated Journal Phys Rev B
Volume 95 Issue 95 Pages 205414
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The effects of external electric and magnetic fields on the energy spectrum of quantum rings made out of a bidimensional semiconductor material with anisotropic band structures are investigated within the effective-mass model. The interplay between the effective-mass anisotropy and the radial confinement leads to wave functions that are strongly localized at two diametrically opposite regions where the kinetic energy is lowest due to the highest effective mass. We show that this quantum phenomenon has clear consequences on the behavior of the energy states in the presence of applied in-plane electric fields and out-of-plane magnetic fields. In the former, the quantum confined Stark effect is observed with either linear or quadratic shifts, depending on the direction of the applied field. As for the latter, the usual Aharonov-Bohm oscillations are not observed for a circularly symmetric confining potential, however they can be reinstated if an elliptic ring with an appropriate aspect ratio is chosen.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000401230600007 Publication Date 2017-05-12
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 19 Open Access
Notes ; This work was financially supported by CNPq under the PRONEX/FUNCAP grants, CAPES Foundation, the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:143746 Serial 4610
Permanent link to this record
 

 
Author Cavalcante, L.S.; Chaves, A.; da Costa, D.R.; Farias, G.A.; Peeters, F.M.
Title All-strain based valley filter in graphene nanoribbons using snake states Type A1 Journal article
Year 2016 Publication (down) Physical review B Abbreviated Journal Phys Rev B
Volume 94 Issue 7 Pages 075432
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A pseudomagnetic field kink can be realized along a graphene nanoribbon using strain engineering. Electron transport along this kink is governed by snake states that are characterized by a single propagation direction. Those pseudomagnetic fields point towards opposite directions in the K and K' valleys, leading to valley polarized snake states. In a graphene nanoribbon with armchair edges this effect results in a valley filter that is based only on strain engineering. We discuss how to maximize this valley filtering by adjusting the parameters that define the stress distribution along the graphene ribbon.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000381889300002 Publication Date 2016-08-23
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 29 Open Access
Notes ; Discussions with R. Grassi are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq), under the PRONEX/FUNCAP and Science Without Borders (SWB) programs, CAPES, the Lemann Foundation, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:144667 Serial 4639
Permanent link to this record
 

 
Author Moura, V.N.; Dantas, D.S.; Farias, G.A.; Chaves, A.; Milošević, M.V.
Title Latent superconductivity at parallel interfaces in a superlattice dominated by another collective quantum phase Type A1 Journal article
Year 2022 Publication (down) Physical review B Abbreviated Journal Phys Rev B
Volume 106 Issue 1 Pages 014516-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We theoretically examine behavior of superconductivity at parallel interfaces separating the domains of another dominant collective excitation, such as charge density waves or spin density waves. Due to their competitive coupling in a two-component Ginzburg-Landau model, suppression of the dominant order parameter at the interfacial planes allows for nucleation of the (hidden) superconducting order parameter at those planes. In such a case, we demonstrate how the number of the parallel interfacial planes and the distance between them are linked to the number and the size of the emerging superconducting gaps in the system, as well as the versatility and temperature evolution of the possible superconducting phases. These findings bear relevance to a broad selection of known layered superconducting materials, as well as to further design of artificial (e.g., oxide) superlattices, where the interplay between competing order parameters paves the way towards otherwise unattainable superconducting states, some with enhanced superconducting critical temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000834346000004 Publication Date 2022-07-22
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
Impact Factor 3.7 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 3.7
Call Number UA @ admin @ c:irua:189520 Serial 7179
Permanent link to this record
 

 
Author Chaves, A.; Sousa, G.O.; Khaliji, K.; da Costa, D.R.; Farias, G.A.; Low, T.
Title Signatures of subband excitons in few-layer black phosphorus Type A1 Journal article
Year 2021 Publication (down) Physical Review B Abbreviated Journal Phys Rev B
Volume 103 Issue 16 Pages 165428
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recent experimental measurements of light absorption in few-layer black phosphorus (BP) revealed a series of high and sharp peaks, interspersed by pairs of lower and broader features. Here, we propose a theoretical model for these excitonic states in few-layer BP within a continuum approach for the in-plane degrees of freedom and a tight-binding approximation that accounts for interlayer couplings. This yields excitonic transitions between different combinations of the subbands created by the coupled BP layers, which leads to a series of high and low oscillator strength excitonic states, consistent with the experimentally observed bright and dark exciton peaks, respectively. The main characteristics of such subband exciton states, as well as the possibility to control their energies and oscillator strengths via applied electric and magnetic fields, are discussed, towards a full understanding of the excitonic spectrum of few-layer BP and its tunability.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000647175200002 Publication Date 2021-04-28
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 Open Access OpenAccess
Notes Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:178384 Serial 8523
Permanent link to this record
 

 
Author Ramos, I.R.O.; Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.
Title Bilayer crystals of charged magnetic dipoles : structure and phonon spectrum Type A1 Journal article
Year 2012 Publication (down) 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 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 Carvalho, J.C.N.; Nelissen, K.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
Title Diffusion in a quasi-one-dimensional system on a periodic substrate Type A1 Journal article
Year 2012 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 85 Issue 2:1 Pages 021136-021136,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The diffusion of charged particles interacting through a repulsive Yukawa potential, exp(-r/lambda)/r, confined by a parabolic potential in the y direction and subjected to a periodic substrate potential in the x direction is investigated. Langevin dynamic simulations are used to investigate the effect of the particle density, the amplitude of the periodic substrate, and the range of the interparticle interaction potential on the diffusive behavior of the particles. We found that in general the diffusion is suppressed with increasing the amplitude of the periodic potential, but for specific values of the strength of the substrate potential a remarkable increase of the diffusion is found with increasing the periodic potential amplitude. In addition, we found a strong dependence of the diffusion on the specific arrangement of the particles, e. g., single-chain versus multichain configuration. For certain particle configurations, a reentrant behavior of the diffusion is found as a function of the substrate strength due to structural transitions in the ordering of the particles.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000300671500007 Publication Date 2012-02-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 9 Open Access
Notes ; This work was supported by the Brazilian agencies CNPq and FUNCAP (PRONEX-Grant), the Flemish Science Foundation (FWO-Vl), and the bilateral projects between Flanders and Brazil and the Flemish Science Foundation (FWO-VI) and CNPq. ; Approved Most recent IF: 2.366; 2012 IF: 2.313
Call Number UA @ lucian @ c:irua:97203 Serial 698
Permanent link to this record
 

 
Author Munarin, F.F.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
Title Ground state and normal-mode spectra of a two-dimensional system of dipole particles confined in a parabolic trap Type A1 Journal article
Year 2008 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 78 Issue 3 Part 1 Pages 031405-31412
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The ordered configurations of a monolayer of interacting magnetic dipoles confined in a circular parabolic potential are investigated as a function of the dipole moment of the particles. Despite the circular confinement, we find very asymmetric ordered structures like chains and Y-shaped configurations when a magnetic field is applied parallel to the plane of the particles. The normal-mode spectrum of the particles and its dependence on the magnetic field and the strength of the dipole moment of the particles are studied. The vibrational and rotational modes of the spectrum, which are associated with the stability of the system, are investigated in detail. The number of particles is varied and we found different ordering of the particles for different values of the dipole moment and the magnetic field. A ring structure with a large number of particles is observed for high values of the dipole moment of the particles.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000259682700057 Publication Date 2008-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 5 Open Access
Notes Approved Most recent IF: 2.366; 2008 IF: 2.508
Call Number UA @ lucian @ c:irua:103084 Serial 1382
Permanent link to this record
 

 
Author Ferreira, W.P.; Peeters, F.M.; Farias, G.A.
Title Melting and evaporation in classical two-dimensional clusters confined by a Coulomb potential Type A1 Journal article
Year 2005 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 72 Issue 4 Part 1 Pages 041502-41507
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The thermal properties of a two-dimensional classical cluster of negatively charged particles bound by a punctual positive charge are presented. The melting phenomenon is analyzed and the features which characterize such a solid-liquid transition are highlighted. We found that the presence of metastable states strongly modifies the melting scenario, and that the melting temperature of the system is determined by the height of the saddle point energy separating the ground state and the metastable state. Due to the particular type of confinement potential considered in this paper, we also found that, at sufficiently large temperature, the cluster can become thermally ionized.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000232930600030 Publication Date 2005-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 4 Open Access
Notes Approved Most recent IF: 2.366; 2005 IF: 2.418
Call Number UA @ lucian @ c:irua:104067 Serial 1983
Permanent link to this record
 

 
Author Ferreira, W.P.; Matulis, A.; Farias, G.A.; Peeters, F.M.
Title Structure and correlations in two-dimensional classical artificial atoms confined by a Coulomb potential Type A1 Journal article
Year 2003 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 67 Issue 4Part 2 Pages 046601-46608
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The ordering of N equally charged particles (-e) moving in two dimensions and confined by a Coulomb potential, resulting from a displaced positive charge Ze is discussed. This is a classical model system for atoms. We obtain the configurations of charged particles which, depending on the value of N and Z, may result in ring structures, hexagonal-type configurations, and for N/Z approximate to 1 in an inner structure of particles which is separated by an outer ring of particles. For N/Z << 1, the Hamiltonian of the parabolic confinement case is recovered. For N/Z approximate to 1, the configurations are very different from those found in the case of a parabolic confinement potential. A hydrodynamic analysis is presented in order to highlight the correlations effects.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000182825400087 Publication Date 2003-04-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-651X;1095-3787; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 14 Open Access
Notes Approved Most recent IF: 2.366; 2003 IF: 2.202
Call Number UA @ lucian @ c:irua:104123 Serial 3273
Permanent link to this record
 

 
Author Ferreira, W.P.; Munarin, F.F.; Nelissen, K.; Costa, R.N.; Peeters, F.M.; Farias, G.A.
Title Structure, normal mode spectra, and mixing of a binary system of charged particles confined in a parabolic trap Type A1 Journal article
Year 2005 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 72 Issue 2 Part 1 Pages 021406-21413
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the mixing of two different kinds of particles, having different charge and/or mass, interacting through a pure Coulomb potential, and confined in a parabolic trap. The structure of the cluster and its normal mode spectrum are analyzed as a function of the ratio of the charges (mass ratio) of the two types of particles. We show that particles are not always arranged in a shell structure. Mixing of the particles goes hand in hand with a large number of metastable states. The normal modes of the system are obtained, and we find that some of the special modes can be tuned by varying the ratio between the charges (masses) of the two species. The degree of mixing of the two type of particles is summarized in a phase diagram, and an order parameter that describes quantitatively the mixing between particles is defined.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000231564000031 Publication Date 2005-08-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 25 Open Access
Notes Approved Most recent IF: 2.366; 2005 IF: 2.418
Call Number UA @ lucian @ c:irua:103149 Serial 3306
Permanent link to this record
 

 
Author Lucena, D.; Tkachenko, D.V.; Nelissen, K.; Misko, V.R.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
Title Transition from single-file to two-dimensional diffusion of interacting particles in a quasi-one-dimensional channel Type A1 Journal article
Year 2012 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 85 Issue 3:1 Pages 031147-031147,12
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Diffusive properties of a monodisperse system of interacting particles confined to a quasi-one-dimensional channel are studied using molecular dynamics simulations. We calculate numerically the mean-squared displacement (MSD) and investigate the influence of the width of the channel (or the strength of the confinement potential) on diffusion in finite-size channels of different shapes (i.e., straight and circular). The transition from single-file diffusion to the two-dimensional diffusion regime is investigated. This transition [ regarding the calculation of the scaling exponent (alpha) of the MSD <Delta x(2)(t)> proportional to t(alpha)] as a function of the width of the channel is shown to change depending on the channel's confinement profile. In particular, the transition can be either smooth (i.e., for a parabolic confinement potential) or rather sharp (i.e., for a hard-wall potential), as distinct from infinite channels where this transition is abrupt. This result can be explained by qualitatively different distributions of the particle density for the different confinement potentials.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000302117900003 Publication Date 2012-03-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 38 Open Access
Notes ; This work was supported by CNPq, FUNCAP (Pronex grant), the “Odysseus” program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the collaborative program CNPq-FWO-Vl. ; Approved Most recent IF: 2.366; 2012 IF: 2.313
Call Number UA @ lucian @ c:irua:97784 Serial 3699
Permanent link to this record
 

 
Author Lucena, D.; Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.
Title Tunable diffusion of magnetic particles in a quasi-one-dimensional channel Type A1 Journal article
Year 2013 Publication (down) Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 87 Issue 1 Pages 012307-12309
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The diffusion of a system of ferromagnetic dipoles confined in a quasi-one-dimensional parabolic trap is studied using Brownian dynamics simulations. We show that the dynamics of the system is tunable by an in-plane external homogeneous magnetic field. For a strong applied magnetic field, we find that the mobility of the system, the exponent of diffusion, and the crossover time among different diffusion regimes can be tuned by the orientation of the magnetic field. For weak magnetic fields, the exponent of diffusion in the subdiffusive regime is independent of the orientation of the external field. DOI: 10.1103/PhysRevE.87.012307
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000314152300005 Publication Date 2013-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 11 Open Access
Notes ; This work was supported by CNPq, CAPES, FUNCAP (Pronex grant), the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, the collaborative program CNPq – FWO-Vl, and the Brazilian program Science Without Borders (CsF). Discussions with V. R. Misko are gratefully acknowledged. ; Approved Most recent IF: 2.366; 2013 IF: 2.326
Call Number UA @ lucian @ c:irua:110089 Serial 3739
Permanent link to this record
 

 
Author Munarin, F.F.; Nelissen, K.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M.
Title Hysteresis and reentrant melting of a self-organized system of classical particles confined in a parabolic trap Type A1 Journal article
Year 2008 Publication (down) Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 77 Issue Pages 031608,1-8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000254539700087 Publication Date 2008-04-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 11 Open Access
Notes Approved Most recent IF: 2.366; 2008 IF: 2.508
Call Number UA @ lucian @ c:irua:69640 Serial 1544
Permanent link to this record
 

 
Author Kong, M.; Vagov, A.; Partoens, B.; Peeters, F.M.; Ferreira, W.P.; Farias, G.A.
Title Nonlinear screening in large two-dimensional Coulomb clusters Type A1 Journal article
Year 2004 Publication (down) Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 70 Issue Pages 051807,1-6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000225970500071 Publication Date 2004-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 4 Open Access
Notes Approved Most recent IF: 2.366; 2004 IF: NA
Call Number UA @ lucian @ c:irua:62444 Serial 2358
Permanent link to this record
 

 
Author Ferreira, W.P.; Peeters, F.M.; Farias, G.A.
Title Normal mode spectra of two-dimensional classical atoms confined by a Coulomb potential Type A1 Journal article
Year 2003 Publication (down) Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 68 Issue Pages 066405,1-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000188316700078 Publication Date 2003-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-651X;1095-3787; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 9 Open Access
Notes Approved Most recent IF: 2.366; 2003 IF: 2.202
Call Number UA @ lucian @ c:irua:69416 Serial 2368
Permanent link to this record
 

 
Author Ferreira, W.P.; Partoens, B.; Peeters, F.M.; Farias, G.A.
Title Structural phase transitions and unusual melting behavior in a classical two-dimensional Coulomb bound cluster Type A1 Journal article
Year 2005 Publication (down) Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 71 Issue Pages 021501,1-4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000228245700023 Publication Date 2005-02-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 8 Open Access
Notes Approved Most recent IF: 2.366; 2005 IF: 2.418
Call Number UA @ lucian @ c:irua:62445 Serial 3251
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 (down) Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue 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 Chaves, A.; Farias, G.A.; Peeters, F.M.; Szafran, B.
Title Wave packet dynamics in semiconductor quantum rings of finite width Type A1 Journal article
Year 2009 Publication (down) Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 80 Issue 12 Pages 125331,1-125331,14
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The time evolution of a wave packet injected into a semiconductor quantum ring is investigated in order to obtain the transmission and reflection probabilities. Within the effective-mass approximation, the time-dependent Schrödinger equation is solved for a system with nonzero width of the ring and leads and finite potential-barrier heights, where we include smooth lead-ring connections. In the absence of a magnetic field, an analysis of the projection of the wave function over the different subband states shows that when the injected wave packet is within a single subband, the junction can scatter this wave packet into different subbands but remarkably at the second junction the wave packet is scattered back into the subband state of the incoming wave packet. If a magnetic field is applied perpendicularly to the ring plane, transmission and reflection probabilities exhibit Aharonov-Bohm (AB) oscillations and the outgoing electrons may end up in different subband states from those of the incoming electrons. Localized impurities, placed in the ring arms, influence the AB oscillation period and amplitude. For a single impurity or potential barrier of sufficiently strong strength, the period of the AB oscillations is halved while for two impurities localized in diametrically opposite points of the ring, the original AB period is recovered. A theoretical investigation of the confined states and time evolution of wave packets in T wires is also made, where a comparison between this system and the lead-ring junction is drawn.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000270383300098 Publication Date 2009-09-25
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 40 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:79231 Serial 3906
Permanent link to this record
 

 
Author Farias, G.A.; da Costa, W.B.; Peeters, F.M.
Title Acoustical polarons and bipolarons in two dimensions Type A1 Journal article
Year 1996 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 54 Issue Pages 12835-12840
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1996VT68200039 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 30 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:15790 Serial 54
Permanent link to this record
 

 
Author Degani, M.H.; Farias, G.A.; Peeters, F.M.
Title Bound states and lifetime of an electron on a bulk helium surface Type A1 Journal article
Year 2005 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 72 Issue 12 Pages 125408-125408,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We propose an effective potential for an excess electron near the helium liquid-vapor interface that takes into account the diffuseness of the liquid-vapor interface and the classical image potential. The splitting of the first two excited states of the excess electron bound to the helium liquid-vapor interface as a function of an external constant electric field applied perpendicular to the interface is in excellent agreement with recent experiments. The effect of a parallel magnetic field on the energy levels are calculated. Single-electron tunneling of the electron out of its surface state is studied as a function of the electric field applied to the system. We found that the tunneling time has a linear dependence on the electric field.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000232229400125 Publication Date 2005-09-06
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 11 Open Access
Notes Approved Most recent IF: 3.836; 2005 IF: 3.185
Call Number UA @ lucian @ c:irua:94719 Serial 251
Permanent link to this record
 

 
Author de Sousa, A.A.; Chaves, A.; Farias, G.A.; Peeters, F.M.
Title Braess paradox at the mesoscopic scale Type A1 Journal article
Year 2013 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 88 Issue 24 Pages 245417-6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We theoretically demonstrate that the transport inefficiency recently found experimentally for branched-out mesoscopic networks can also be observed in a quantum ring of finite width with an attached central horizontal branch. This is done by investigating the time evolution of an electron wave packet in such a system. Our numerical results show that the conductivity of the ring does not necessary improve if one adds an extra channel. This ensures that there exists a quantum analog of the Braess paradox, originating from quantum scattering and interference.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000328680500011 Publication Date 2013-12-17
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 17 Open Access
Notes ; This work was financially supported by PRONEX/CNPq/FUNCAP and the bilateral project CNPq-FWO. Discussions with J. S. Andrade, Jr. are gratefully acknowledged. A. A. S. has been financially supported by CAPES, under PDSE Contract No. BEX 7177/13-5. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:113705 Serial 253
Permanent link to this record
 

 
Author Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.
Title Chiral states in bilayer graphene : magnetic field dependence and gap opening Type A1 Journal article
Year 2011 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 12 Pages 125451-125451,13
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract At the interface of electrostatic potential kink profiles, one-dimensional chiral states are found in bilayer graphene (BLG). Such structures can be created by applying an asymmetric potential to the upper and the lower layers of BLG. We found the following: (i) due to the strong confinement by the single kink profile, the unidirectional states are only weakly affected by a magnetic field; (ii) increasing the smoothness of the kink potential results in additional bound states, which are topologically different from those chiral states; and (iii) in the presence of a kink-antikink potential, the overlap between the oppositely moving chiral states results in the appearance of crossing and anticrossing points in the energy spectrum. This leads to the opening of tunable minigaps in the spectrum of the unidirectional topological states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000295484300016 Publication Date 2011-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 50 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92915 Serial 358
Permanent link to this record
 

 
Author Chaves, A.; Komendová, L.; Milošević, M.V.; Andrade, J.S.; Farias, G.A.; Peeters, F.M.
Title Conditions for nonmonotonic vortex interaction in two-band superconductors Type A1 Journal article
Year 2011 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 21 Pages 214523-214523,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We describe a semianalytic approach to the two-band Ginzburg-Landau theory, which predicts the behavior of vortices in two-band superconductors. We show that the character of the short-range vortex-vortex interaction is determined by the sign of the normal domain-superconductor interface energy, in analogy with the conventional differentiation between type I and type II superconductors. However, we also show that the long-range interaction is determined by a modified Ginzburg-Landau parameter κ*, different from the standard κ of a bulk superconductor. This opens the possibility for nonmonotonic vortex-vortex interaction, which is temperature dependent, and can be further tuned by alterations of the material on the microscopic scale.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000292252300009 Publication Date 2011-06-30
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 46 Open Access
Notes ; Discussions with A. Moreira, A. Shanenko, R. Prozorov, and A. Golubov are gratefully acknowledged. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral project FWO-CNPq, CAPES, and PRONEX/CNPq/FUNCAP. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:90922 Serial 477
Permanent link to this record