Records |
Author |
Petrovic, M.D.; Peeters, F.M.; Chaves, A.; Farias, G.A. |
Title |
Conductance maps of quantum rings due to a local potential perturbation |
Type |
A1 Journal article |
Year |
2013 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
25 |
Issue |
49 |
Pages |
495301-495309 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the phi(0) periodic Aharonov-Bohm oscillation pattern into a phi(0)/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000327181400002 |
Publication Date |
2013-11-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
12 |
Open Access |
|
Notes |
; This work was supported by the Methusalem programme of the Flemish government, the CNPq-FWO bilateral programme and PNPD and FUNCAP/PRONEX grants. ; |
Approved |
Most recent IF: 2.649; 2013 IF: 2.223 |
Call Number |
UA @ lucian @ c:irua:112694 |
Serial |
478 |
Permanent link to this record |
|
|
|
Author |
Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.; Costa Filho, R.N. |
Title |
The electronic properties of graphene and graphene ribbons under simple shear strain |
Type |
A1 Journal article |
Year |
2012 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
37 |
Pages |
375301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000308202700011 |
Publication Date |
2012-08-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by CNPq (RNCF), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:101838 |
Serial |
1000 |
Permanent link to this record |
|
|
|
Author |
Freire, J.A.K.; Peeters, F.M.; Freire, V.N.; Farias, G.A. |
Title |
Exciton trapping in magnetic wire structures |
Type |
A1 Journal article |
Year |
2001 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
13 |
Issue |
|
Pages |
3283-3295 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000168269200006 |
Publication Date |
2002-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2001 IF: 1.611 |
Call Number |
UA @ lucian @ c:irua:37302 |
Serial |
1121 |
Permanent link to this record |
|
|
|
Author |
Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.; |
Title |
Melting of a two-dimensional binary cluster of charged particles confined in a parabolic trap |
Type |
A1 Journal article |
Year |
2006 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
18 |
Issue |
41 |
Pages |
9385-9401 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000241277900011 |
Publication Date |
2006-09-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2006 IF: 2.038 |
Call Number |
UA @ lucian @ c:irua:61314 |
Serial |
1985 |
Permanent link to this record |
|
|
|
Author |
Ferreira, W.P.; Farias, G.A.; Peeters, F.M. |
Title |
A two-component mixture of charged particles confined in a channel: melting |
Type |
A1 Journal article |
Year |
2010 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
22 |
Issue |
28 |
Pages |
11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The melting of a binary system of charged particles confined in a quasi-one-dimensional parabolic channel is studied through Monte Carlo simulations. At zero temperature the particles are ordered in parallel chains. The melting is anisotropic and different melting temperatures are obtained according to the spatial direction, and the different kinds of particles present in the system. Melting is very different for the single-, two- and four-chain configurations. A temperature induced structural phase transition is found between two different four-chain ordered states which is absent in the mono-disperse system. In the mixed regime, where the two kinds of particles are only slightly different, melting is almost isotropic and a thermally induced homogeneous distribution of the distinct kinds of charges is observed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000279257300023 |
Publication Date |
2010-06-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by CNPq, the Flemish Science Foundation (FWO-V1) and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2010 IF: 2.332 |
Call Number |
UA @ lucian @ c:irua:83862 |
Serial |
3771 |
Permanent link to this record |
|
|
|
Author |
Pereira, J.M.; Peeters, F.M.; Costa Filho, R.N.; Farias, G.A. |
Title |
Valley polarization due to trigonal warping on tunneling electrons in graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
21 |
Issue |
4 |
Pages |
045301,1-045301,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of trigonal warping on the transmission of electrons tunneling through potential barriers in graphene is investigated. We present calculations of the transmission coefficient for single and double barriers as a function of energy, incidence angle and barrier heights. The results show remarkable valley-dependent directional effects for barriers oriented parallel to the armchair or parallel to the zigzag direction. These results indicate that electrostatic gates can be used as valley filters in graphene-based devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000262354700004 |
Publication Date |
2008-12-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
78 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
Call Number |
UA @ lucian @ c:irua:75736 |
Serial |
3834 |
Permanent link to this record |
|
|
|
Author |
Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
Title |
Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers |
Type |
A1 Journal article |
Year |
2011 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
23 |
Issue |
27 |
Pages |
275801,1-275801,16 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000291993600009 |
Publication Date |
2011-06-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
32 |
Open Access |
|
Notes |
; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
Call Number |
UA @ lucian @ c:irua:90880 |
Serial |
3908 |
Permanent link to this record |
|
|
|
Author |
da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
Title |
Valley filtering in graphene due to substrate-induced mass potential |
Type |
A1 Journal article |
Year |
2017 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of physics : condensed matter |
Abbreviated Journal |
|
Volume |
29 |
Issue |
21 |
Pages |
215502 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The interaction of monolayer graphene with specific substrates may break its sublattice symmetry and results in unidirectional chiral states with opposite group velocities in the different Dirac cones (Zarenia et al 2012 Phys. Rev. B 86 085451). Taking advantage of this feature, we propose a valley filter based on a transversal mass kink for low energy electrons in graphene, which is obtained by assuming a defect region in the substrate that provides a change in the sign of the substrate-induced mass and thus creates a non-biased channel, perpendicular to the kink, for electron motion. By solving the time-dependent Schrodinger equation for the tight-binding Hamiltonian, we investigate the time evolution of a Gaussian wave packet propagating through such a system and obtain the transport properties of this graphene-based substrate-induced quantum point contact. Our results demonstrate that efficient valley filtering can be obtained, provided: (i) the electron energy is sufficiently low, i.e. with electrons belonging mostly to the lowest sub-band of the channel, and (ii) the channel length (width) is sufficiently long (narrow). Moreover, even though the transmission probabilities for each valley are significantly affected by impurities and defects in the channel region, the valley polarization in this system is shown to be robust against their presence. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000400092700002 |
Publication Date |
2017-04-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
15 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:152636 |
Serial |
8730 |
Permanent link to this record |
|
|
|
Author |
Freire, J.A.K.; Matulis, A.; Peeters, F.M.; Freire, V.N.; Farias, G.A. |
Title |
Exciton trapping in a hybrid ferromagnetic/semiconductor magnetic antidot |
Type |
A1 Journal article |
Year |
2001 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of magnetism and magnetic materials |
Abbreviated Journal |
J Magn Magn Mater |
Volume |
226/230 |
Issue |
|
Pages |
2038-2039 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000170628400349 |
Publication Date |
2002-07-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-8853; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.63 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.63; 2001 IF: 1.329 |
Call Number |
UA @ lucian @ c:irua:37314 |
Serial |
1119 |
Permanent link to this record |
|
|
|
Author |
Dantas, D.S.; Chaves, A.; Farias, G.A.; Ramos, A.C.A.; Peeters, F.M. |
Title |
Low-dimensional confining structures on the surface of helium films suspended on designed cavities |
Type |
A1 Journal article |
Year |
2013 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of low temperature physics |
Abbreviated Journal |
J Low Temp Phys |
Volume |
173 |
Issue |
3-4 |
Pages |
207-226 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the formation of quantum confined structures on the surface of a liquid helium film suspended on a nanostructured substrate. We show theoretically that, by nanostructuring the substrate, it is possible to change the geometry of the liquid helium surface, opening the possibility of designing and controlling the formation of valleys with different shapes. By applying an external electric field perpendicular to the substrate plane, surface electrons can be trapped into these valleys, as in a quantum dot. We investigate how the external parameters, such as the electric field strength and the height of the liquid helium bath, can be tuned to control the energy spectrum of the trapped surface electrons. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York |
Editor |
|
Language |
|
Wos |
000324820300008 |
Publication Date |
2013-08-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-2291;1573-7357; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.3 |
Times cited |
1 |
Open Access |
|
Notes |
; This work has received financial support from the Brazilian National Research Council (CNPq), Fundacao Cearense de Apoio ao Desenvolvimento Cientifico e Tecnologico (Funcap), CAPES and Pronex/CNPq/Funcap. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the bilateral project between CNPq and FWO-Vl. ; |
Approved |
Most recent IF: 1.3; 2013 IF: 1.036 |
Call Number |
UA @ lucian @ c:irua:111140 |
Serial |
1845 |
Permanent link to this record |
|
|
|
Author |
de Sousa, J.S.; Covaci, L.; Peeters, F.M.; Farias, G.A. |
Title |
Time-dependent investigation of charge injection in a quantum dot containing one electron |
Type |
A1 Journal article |
Year |
2012 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
112 |
Issue |
9 |
Pages |
093705-93709 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The interaction of an injected electron towards a quantum dot (QD) containing a single confined electron is investigated using a flexible time-dependent quantum mechanics formalism, which allows both electrons to move and undergo quantum transitions. Different scenarios combining quantum dot dimensions, dielectric constant, injected wave packet energy, and width were explored, and our main results are: (i) due to the large characteristic transitions times between the confined state in the quantum dot and the delocalized state in the continuum, it is relatively difficult to ionize the occupied QD by Coulomb interaction solely and (ii) the charging state of the quantum dot can be sensed by direct injection of charges. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4759292] |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000311968400052 |
Publication Date |
2012-11-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was financially supported by the Brazilian National Research Council (CNPq), under Contract No. NanoBioEstruturas 555183/2005-0, Fundao Cearense de Apoio ao Desenvolvimento Cientfico e Tecnolgico (Funcap), CAPES, Pronex/CNPq/ Funcap, the Bilateral program between Flanders and Brazil, and the Flemish Science Foundation (FWO). ; |
Approved |
Most recent IF: 2.068; 2012 IF: 2.210 |
Call Number |
UA @ lucian @ c:irua:106014 |
Serial |
3664 |
Permanent link to this record |
|
|
|
Author |
de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. |
Title |
Quantum tunneling between bent semiconductor nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
174301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000364584200020 |
Publication Date |
2015-11-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
|
Notes |
; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:129544 |
Serial |
4234 |
Permanent link to this record |
|
|
|
Author |
Frota, D.A.; Chaves, A.; Ferreira, W.P.; Farias, G.A.; Milošević, M.V. |
Title |
Superconductor-ferromagnet bilayer under external drive : the role of vortex-antivortex matter |
Type |
A1 Journal article |
Year |
2016 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
119 |
Issue |
119 |
Pages |
093912 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using advanced Ginzburg-Landau simulations, we study the superconducting state of a thin superconducting film under a ferromagnetic layer, separated by an insulating oxide, in applied external magnetic field and electric current. The taken uniaxial ferromagnet is organized into a series of parallel domains with alternating polarization of out-of-plane magnetization, sufficiently strong to induce vortex-antivortex pairs in the underlying superconductor in absence of other magnetic field. We show the organization of such vortex-antivortex matter into rich configurations, some of which are not matching the periodicity of the ferromagnetic film. The variety of possible configurations is enhanced by applied homogeneous magnetic field, where additional vortices in the superconductor may lower the energy of the system by either annihilating the present antivortices under negative ferromagnetic domains or by lowering their own energy after positioning under positive ferromagnetic domains. As a consequence, both the vortex-antivortex reordering in increasing external field and the evolution of the energy of the system are highly nontrivial. Finally, we reveal the very interesting effects of applied dc electric current on the vortex-antivortex configurations, since resulting Lorentzian force has opposite direction for vortices and antivortices, while direction of the applied current with respect to ferromagnetic domains is of crucial importance for the interaction of the applied and the Meissner current, as well as the consequent vortex-antivortex dynamics-both of which are reflected in the anisotropic critical current of the system. (C) 2016 AIP Publishing LLC. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000372351900018 |
Publication Date |
2016-03-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the Brazilian agencies CNPq, PRONEX/FUNCAP, and CAPES, and the Research Foundation-Flanders (FWO). ; |
Approved |
Most recent IF: 2.068 |
Call Number |
UA @ lucian @ c:irua:133200 |
Serial |
4255 |
Permanent link to this record |
|
|
|
Author |
Chaves, A.; Farias, G.A.; Peeters, F.M.; Ferreira, R. |
Title |
The Split-operator technique for the study of spinorial wavepacket dynamics |
Type |
A1 Journal article |
Year |
2015 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Communications in computational physics |
Abbreviated Journal |
Commun Comput Phys |
Volume |
17 |
Issue |
17 |
Pages |
850-866 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The split-operator technique for wave packet propagation in quantum systems is expanded here to the case of propagatingwave functions describing Schrodinger particles, namely, charge carriers in semiconductor nanostructures within the effective mass approximation, in the presence of Zeeman effect, as well as of Rashba and Dresselhaus spin-orbit interactions. We also demonstrate that simple modifications to the expanded technique allow us to calculate the time evolution of wave packets describing Dirac particles, which are relevant for the study of transport properties in graphene. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000353695400010 |
Publication Date |
2015-03-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1815-2406;1991-7120; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.004 |
Times cited |
24 |
Open Access |
|
Notes |
; The authors gratefully acknowledge fruitful discussions with J. M. Pereira Jr. and R. N. Costa Filho. This work was financially supported by CNPq through the INCT-NanoBioSimes and the Science Without Borders programs (contract 402955/ 2012-9), PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.004; 2015 IF: 1.943 |
Call Number |
c:irua:126028 |
Serial |
3593 |
Permanent link to this record |
|
|
|
Author |
da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
Title |
Analytical study of the energy levels in bilayer graphene quantum dots |
Type |
A1 Journal article |
Year |
2014 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
78 |
Issue |
|
Pages |
392-400 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the four-band continuum model we derive a general expression for the infinite-mass boundary condition in bilayer graphene. Applying this new boundary condition we analytically calculate the confined states and the corresponding wave functions in a bilayer graphene quantum dot in the absence and presence of a perpendicular magnetic field. Our results for the energy spectrum show an energy gap between the electron and hole states at small magnetic fields. Furthermore the electron (e) and hole (h) energy levels corresponding to the K and K' valleys exhibit the E-K(e(h)) (m) = E-K'(e(h)) (m) symmetry, where m is the angular momentum quantum number. (C) 2014 Elsevier Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000341463900042 |
Publication Date |
2014-07-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
35 |
Open Access |
|
Notes |
; This work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the process number BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program Euro-GRAPHENE (project CONGRAN), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). We thank M. Ramezani Masir and M. Grujic for helpful comments and discussions. ; |
Approved |
Most recent IF: 6.337; 2014 IF: 6.196 |
Call Number |
UA @ lucian @ c:irua:119280 |
Serial |
109 |
Permanent link to this record |
|
|
|
Author |
Shi, J.M.; Farias, G.A.; Koenraad, P.M.; van de Stadt, A.F.W.; Peeters, F.M.; Wolter, J.H.; Devreese, J.T. |
Title |
Correlation effects of DX centers on electron mobility in delta doped semiconductors investigated by Monte Carlo simulations |
Type |
A1 Journal article |
Year |
1997 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Brazilian journal of physics |
Abbreviated Journal |
Braz J Phys |
Volume |
27 |
Issue |
A |
Pages |
327-331 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
São Paulo |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0103-9733 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
0.732 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.732; 1997 IF: NA |
Call Number |
UA @ lucian @ c:irua:19298 |
Serial |
525 |
Permanent link to this record |
|
|
|
Author |
Freire, J.A.K.; Freire, V.N.; Farias, G.A.; Peeters, F.M. |
Title |
Exciton trapping in a periodically modulated magnetic field |
Type |
A1 Journal article |
Year |
2002 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Brazilian journal of physics |
Abbreviated Journal |
Braz J Phys |
Volume |
32 |
Issue |
2 |
Pages |
310-313 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The behavior of excitons in spatially modulated magnetic fields is described taking into account the exciton spin contribution. The results show that the exciton trapping in periodic magnetic fields is possible and dependent on the modulation profile. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
São Paulo |
Editor |
|
Language |
|
Wos |
000176522000016 |
Publication Date |
2005-04-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0103-9733; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.732 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.732; 2002 IF: 0.678 |
Call Number |
UA @ lucian @ c:irua:94923 |
Serial |
1120 |
Permanent link to this record |
|
|
|
Author |
Xavier, L.J.P.; Pereira, J.M.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
Title |
Topological confinement in graphene bilayer quantum rings |
Type |
A1 Journal article |
Year |
2010 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
96 |
Issue |
21 |
Pages |
212108,1-212108,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We find localized electron and hole states in a ring-shaped potential kink in biased bilayer graphene. Within the continuum description, we show that for sharp potential steps the Dirac equation describing carrier states close to the K (or K′) point of the first Brillouin zone can be solved analytically for a circular kink/antikink dot. The solutions exhibit interfacial states which exhibit AharonovBohm oscillations as functions of the height of the potential step and/or the radius of the ring. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000278183200039 |
Publication Date |
2010-05-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
29 |
Open Access |
|
Notes |
; This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, FUNCAP, CAPES, the Bilateral program between Flanders and Brazil, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
Call Number |
UA @ lucian @ c:irua:83373 |
Serial |
3675 |
Permanent link to this record |
|
|
|
Author |
Freire, J.A.K.; Peeters, F.M.; Matulis, A.; Freire, V.N.; Farias, G.A. |
Title |
Magnetic traps for excitons in GaAs/AlxGa1-xAs quantum wells |
Type |
P1 Proceeding |
Year |
2001 |
Publication ![sorted by Publication field, descending order (down)](img/sort_desc.gif) |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
503-504 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Springer |
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:37299 |
Serial |
1890 |
Permanent link to this record |