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Author (up) 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 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 (up) Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M.; Axt, V.M. url  doi
openurl 
  Title Parity-fluctuation induced enlargement of the ratio \DeltaE/kBTc in metallic grains Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 84 Issue 21 Pages 214518-214518,12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate how the interplay of quantum confinement and particle number-parity fluctuations affects superconducting correlations in ultra-small metallic grains. Using the number-parity projected BCS formalism we calculate the critical temperature and the excitation gap as a function of the grain size for grains with even and odd number of confined carriers. We show that the experimentally observed anomalous increase of the coupling ratio ΔE/kBTc with decreasing superconducting grain size can be attributed to an enhancement of the number-parity fluctuations in ultra-small grains.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000298114100003 Publication Date 2011-12-16  
  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 14 Open Access  
  Notes ; This work was supported by the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flamish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). M. D. C. thanks A. S. Mel'nikov and N. B. Kopnin for fruitful discussions. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:94373 Serial 2555  
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Author (up) Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. url  doi
openurl 
  Title Phonon limited superconducting correlations in metallic nanograins Type A1 Journal article
  Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 5 Issue 5 Pages 16515  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000364647700001 Publication Date 2015-11-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 9 Open Access  
  Notes ; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; Approved Most recent IF: 4.259; 2015 IF: 5.578  
  Call Number UA @ lucian @ c:irua:129543 Serial 4224  
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Author (up) Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Vasenko, A.S.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. pdf  doi
openurl 
  Title Influence of disorder on superconducting correlations in nanoparticles Type A1 Journal article
  Year 2016 Publication Journal of superconductivity and novel magnetism Abbreviated Journal J Supercond Nov Magn  
  Volume 29 Issue 29 Pages 605-609  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate how the interplay of quantum confinement and level broadening caused by disorder affects superconducting correlations in ultra-small metallic grains. We use the electron-phonon interaction-induced electron mass renormalization and the reduced static-path approximation of the BCS formalism to calculate the critical temperature as a function of the grain size. We show how the strong electron-impurity scattering additionally smears the peak structure in the electronic density of states of a metallic grain and imposes additional limits on the critical temperature under strong quantum confinement.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000371089500013 Publication Date 2016-01-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1557-1939 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.18 Times cited 7 Open Access  
  Notes ; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Flemish Science Foundation (FWO-Vl), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO-Vl. ; Approved Most recent IF: 1.18  
  Call Number UA @ lucian @ c:irua:132286 Serial 4195  
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Author (up) 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 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  
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Author (up) Čukarić, N.; Tadić, M.; Peeters, F.M. doi  openurl
  Title Electron and hole states in a quantum ring grown by droplet epitaxy. Influence of the layer inside the ring opening Type A1 Journal article
  Year 2010 Publication Superlattices and microstructures Abbreviated Journal Superlattice Microst  
  Volume 48 Issue 5 Pages 491-501  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic structure of the conduction and valence bands of a quantum ring containing a layer inside the ring opening is modeled This structure (nanocup) consists of a GaAs nanodisk (the cup s bottom) and a GaAs nanoring (the cup s rim) which encircles the disk The whole system is embedded in an (Al Ga)As matrix and its shape resembles realistic ring structures grown by the droplet epitaxy technique The conduction-band states in the structure are modeled by the single-band effective-mass theory while the 4-band Luttinger-Kohn model is adopted to compute the valence-band states We analyze how the electronic structure of the nanocup evolves from the one of a quantum ring when the size of either the nanodisk or the nanoring is changed For that purpose (1) the width of the ring (2) the disk radius and (3) the disk height are separately varied For dimensions typical for experimentally realized structures we find that the electron wavefunctions are mainly localized inside the ring even when the thickness of the Inner layer is 90% of the ring thickness These calculations indicate that topological phenomena like the excitonic Aharonov-Bohm effect are negligibly affected by the presence of the layer inside the ring (C) 2010 Elsevier Ltd All rights reserved  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000284521400005 Publication Date 2010-09-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0749-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.123 Times cited 9 Open Access  
  Notes ; The authors would like to thank Prof B Partoens for useful discussions This work was supported by the EU NoE SANDiE the Ministry of Science of Serbia the Flemish Science Foundation (FWO-VI) and the Belgian Science Policy (IAP) ; Approved Most recent IF: 2.123; 2010 IF: 1.096  
  Call Number UA @ lucian @ c:irua:95551 Serial 906  
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Author (up) Cukaric, N.A.; Partoens, B.; Tadic, M.Z.; Arsoski, V.V.; Peeters, F.M. pdf  doi
openurl 
  Title The 30-band k . p theory of valley splitting in silicon thin layers Type A1 Journal article
  Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 28 Issue 28 Pages 195303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The valley splitting of the conduction-band states in a thin silicon-on-insulator layer is investigated using the 30-band k . p theory. The system composed of a few nm thick Si layer embedded within thick SiO2 layers is analyzed. The valley split states are found to cross periodically with increasing quantum well width, and therefore the energy splitting is an oscillatory function of the quantum well width, with period determined by the wave vector K-0 of the conduction band minimum. Because the valley split states are classified by parity, the optical transition between the ground hole state and one of those valley split conduction band states is forbidden. The oscillations in the valley splitting energy decrease with electric field and with smoothing of the composition profile between the well and the barrier by diffusion of oxygen from the SiO2 layers to the Si quantum well. Such a smoothing also leads to a decrease of the interband transition matrix elements. The obtained results are well parametrized by the effective two-valley model, but are found to disagree from previous 30-band calculations. This discrepancy could be traced back to the fact that the basis for the numerical solution of the eigenproblem must be restricted to the first Brillouin zone in order to obtain quantitatively correct results for the valley splitting.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000374394700009 Publication Date 2016-04-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 2.649 Times cited Open Access  
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:133610 Serial 4261  
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Author (up) Čukarić, N.A.; Tadić, M.Z.; Partoens, B.; Peeters, F.M. url  doi
openurl 
  Title 30-band k\cdot p model of electron and hole states in silicon quantum wells Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 20 Pages 205306  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We modeled the electron and hole states in Si/SiO2 quantum wells within a basis of standing waves using the 30-band k . p theory. The hard-wall confinement potential is assumed, and the influence of the peculiar band structure of bulk silicon on the quantum-well sub-bands is explored. Numerous spurious solutions in the conduction-band and valence-band energy spectra are found and are identified to be of two types: (1) spurious states which have large contributions of the bulk solutions with large wave vectors (the high-k spurious solutions) and (2) states which originate mainly from the spurious valley outside the Brillouin zone (the extravalley spurious solutions). An algorithm to remove all those nonphysical solutions from the electron and hole energy spectra is proposed. Furthermore, slow and oscillatory convergence of the hole energy levels with the number of basis functions is found and is explained by the peculiar band mixing and the confinement in the considered quantum well. We discovered that assuming the hard-wall potential leads to numerical instability of the hole states computation. Nonetheless, allowing the envelope functions to exponentially decay in a barrier of finite height is found to improve the accuracy of the computed hole states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000327161500007 Publication Date 2013-11-20  
  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 10 Open Access  
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Belgian Science Policy (IAP), the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:112704 Serial 18  
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Author (up) Čukarić, N.A.; Tadić, M.Z.; Partoens, B.; Peeters, F.M. doi  openurl
  Title The interband optical absorption in silicon quantum wells : application of the 30-band k . p model Type A1 Journal article
  Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 104 Issue 24 Pages 242103  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The interband optical absorption in Si/SiO2 quantum wells is calculated as function of the well width (W) and the evolution from an indirect to a direct gap material as function of the well width is investigated. In order to compute the electron states in the conduction band, the 30-band k . p model is employed, whereas the 6-band Luttinger-Kohn model is used for the hole states. We found that the effective direct band gap in the quantum well agrees very well with the W-2 scaling result of the single-band model. The interband matrix elements for linear polarized light oscillate with the quantum well width, which agrees qualitatively with a single band calculation. Our theoretical results indicate that the absorption can be maximized by a proper choice of the well width. However, the obtained absorption coefficients are at least an order of magnitude smaller than for a typical direct semiconductor even for a well width of 2 nm. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000337915000033 Publication Date 2014-06-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 1 Open Access  
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; Approved Most recent IF: 3.411; 2014 IF: 3.302  
  Call Number UA @ lucian @ c:irua:118448 Serial 1689  
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Author (up) Cunha, S.M.; da Costa, D.R.; Pereira, J.M., Jr.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M. url  doi
openurl 
  Title Tunneling properties in α-T₃ lattices : effects of symmetry-breaking terms Type A1 Journal article
  Year 2022 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 105 Issue 16 Pages 165402-165414  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The alpha-T3 lattice model interpolates a honeycomb (graphene-like) lattice and a T3 (also known as dice) lattice via the parameter alpha. These lattices are made up of three atoms per unit cell. This gives rise to an additional dispersionless flat band touching the conduction and valence bands. Electrons in this model are analogous to Dirac fermions with an enlarged pseudospin, which provides unusual tunneling features like omnidirectional Klein tunneling, also called super-Klein tunneling (SKT). However, it is unknown how small deviations in the equivalence between the atomic sites, i.e., variations in the alpha parameter, and the number of tunnel barriers changes the transmission properties. Moreover, it is interesting to learn how tunneling occurs through regions where the energy spectrum changes from linear with a middle flat band to a hyperbolic dispersion. In this paper we investigate these properties, its dependence on the number of square barriers and the alpha parameter for either gapped and gapless cases. Furthermore, we compare these results to the case where electrons tunnel from a region with linear dispersion to a region with a bandgap. In the latter case, contrary to tunneling through a potential barrier, the SKT is no longer observed. Finally, we find specific cases where transmission is allowed due to a symmetry breaking of sublattice equivalence.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000805195200001 Publication Date 2022-04-01  
  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 3.7 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 3.7  
  Call Number UA @ admin @ c:irua:188614 Serial 7222  
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Author (up) Cunha, S.M.; de Costa, D.R.; Pereira Jr, J.M.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M. url  doi
openurl 
  Title Band-gap formation and morphing in alpha-T-3 superlattices Type A1 Journal article
  Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 104 Issue 11 Pages 115409  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Electrons in alpha-T-3 lattices behave as condensed-matter analogies of integer-spin Dirac fermions. The three atoms making up the unit cell bestow the energy spectrum with an additional energy band that is completely flat, providing unique electronic properties. The interatomic hopping term, alpha, is known to strongly affect the electronic spectrum of the two-dimensional (2D) lattice, allowing it to continuously morph from graphenelike responses to the behavior of fermions in a dice lattice. For pristine lattice structures the energy bands are gapless, but small deviations in the atomic equivalence of the three sublattices will introduce gaps in the spectrum. It is unknown how these affect transport and electronic properties such as the energy spectrum of superlattice minibands. Here we investigate the dependency of these properties on the parameter a accounting for different symmetry-breaking terms, and we show how it affects band-gap formation. Furthermore, we find that superlattices can force band gaps to close and shift in energy. Our results demonstrate that alpha-T-3 superlattices provide a versatile material for 2D band-gap engineering purposes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000696091600003 Publication Date 2021-09-10  
  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 6 Open Access OpenAccess  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:181544 Serial 6972  
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Author (up) da Costa, D.R.; Chaves, A.; Farias, G.A.; Covaci, L.; Peeters, F.M. url  doi
openurl 
  Title Wave-packet scattering on graphene edges in the presence of a pseudomagnetic field Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 86 Issue 11 Pages 115434  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The scattering of a Gaussian wave packet in armchair and zigzag graphene edges is theoretically investigated by numerically solving the time-dependent Schrodinger equation for the tight-binding model Hamiltonian. Our theory allows us to investigate scattering in reciprocal space, and depending on the type of graphene edge we observe scattering within the same valley, or between different valleys. In the presence of an external magnetic field, the well-known skipping orbits are observed. However, our results demonstrate that in the case of a pseudomagnetic field, induced by nonuniform strain, the scattering by an armchair edge results in a nonpropagating edge state.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000309174100005 Publication Date 2012-09-21  
  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 28 Open Access  
  Notes ; Discussions with E. B. Barros are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE (project CONGRAN), and the bilateral program between Flanders and Brazil. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:101833 Serial 3907  
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Author (up) da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M. pdf  doi
openurl 
  Title Valley filtering in graphene due to substrate-induced mass potential Type A1 Journal article
  Year 2017 Publication 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  
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Author (up) da Costa, D.R.; Chaves, A.; Sena, S.H.R.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Valley filtering using electrostatic potentials in bilayer graphene Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 045417  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Propagation of an electron wave packet through a quantum point contact (QPC) defined by electrostatic gates in bilayer graphene is investigated. The gates provide a bias between the layers, in order to produce an energy gap. If the gates on both sides of the contact produce the same bias, steps in the electron transmission probability are observed, as in the usual QPC. However, if the bias is inverted on one of the sides of the QPC, only electrons belonging to one of the Dirac valleys are allowed to pass, which provides a very efficient valley filtering.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000358253200009 Publication Date 2015-07-20  
  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 47 Open Access  
  Notes ; This work was financially supported by CNPq, under PNPD and PRONEX/FUNCAP grants; the CAPES Foundation under ProcessNo. BEX7178/13-1; the Bilateral programme between Flanders and Brazil; the Flemish Science Foundation (FWOVl); and the Brazilian program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:127152 Serial 3833  
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Author (up) da Costa, D.R.; Chaves, A.; Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Geometry and edge effects on the energy levels of graphene quantum rings : a comparison between tight-binding and simplified Dirac models Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 89 Issue 7 Pages 075418-12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present a systematic study of the energy spectra of graphene quantum rings having different geometries and edge types in the presence of a perpendicular magnetic field. Results are obtained within the tight-binding (TB) and Dirac models and we discuss which features of the former can be recovered by using the approximations imposed by the latter. Energy levels of graphene quantum rings obtained by diagonalizing the TB Hamiltonian are demonstrated to be strongly dependent on the rings geometry and the microscopical structure of the edges. This makes it difficult to recover those spectra by the existing theories that are based on the continuum (Dirac) model. Nevertheless, our results show that both approaches (i.e., TB and Dirac model) may provide similar results, but only for very specific combinations of ring geometry and edge types. The results obtained by a simplified model describing an infinitely thin circular Dirac ring show good agreement with those obtained for hexagonal and rhombus armchair graphene rings within the TB model. Moreover, we show that the energy levels of a circular quantum ring with an infinite mass boundary condition obtained within the Dirac model agree with those for a ring defined by a ring-shaped staggered potential obtained within the TB model.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000332390000009 Publication Date 2014-02-18  
  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 56 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 Bilateral programme between CNPq and the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:115823 Serial 1328  
Permanent link to this record
 

 
Author (up) da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. pdf  doi
openurl 
  Title Analytical study of the energy levels in bilayer graphene quantum dots Type A1 Journal article
  Year 2014 Publication 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  
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Author (up) da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Magnetic field dependence of energy levels in biased bilayer graphene quantum dots Type A1 Journal article
  Year 2016 Publication 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  
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Author (up) da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Energy levels of bilayer graphene quantum dots Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 115437  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Within a tight binding approach we investigate the energy levels of hexagonal and triangular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We study AA- and AB-(Bernal) stacked BLG QDs and obtain the energy levels in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). Our results show that the size dependence of the energy levels is different from that of monolayer graphene QDs. The energy spectrum of AB-stacked BLG QDs with zigzag edges exhibits edge states which spread out into the opened energy gap in the presence of a perpendicular electric field. We found that the behavior of these edges states is different for the hexagonal and triangular geometries. In the case of AA-stacked BLG QDs, the electron and hole energy levels cross each other in both cases of armchair and zigzag edges as the dot size or the applied bias increases.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000361663700003 Publication Date 2015-09-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 21 Open Access  
  Notes ; This work was 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 Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:128726 Serial 4173  
Permanent link to this record
 

 
Author (up) da Costa, W.B.; Peeters, F.M. doi  openurl
  Title Diagonalization of the generalized Feynman bipolaron model in a magnetic field Type A1 Journal article
  Year 1995 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 7 Issue Pages 1293-1304  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos A1995QJ24700011 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 2.346 Times cited 18 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:12199 Serial 687  
Permanent link to this record
 

 
Author (up) da Costa, W.B.; Peeters, F.M. doi  openurl
  Title Phase diagram for large two dimensional bipolarons in a magnetic field Type A1 Journal article
  Year 1998 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 57 Issue Pages 10569-10575  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000073464500063 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 8 Open Access  
  Notes Approved Most recent IF: 3.836; 1998 IF: NA  
  Call Number UA @ lucian @ c:irua:24168 Serial 2581  
Permanent link to this record
 

 
Author (up) da Costa, W.B.; Peeters, F.M. doi  openurl
  Title The polaron-bipolaron transition for acoustical three-dimensional polarons Type A1 Journal article
  Year 1996 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 8 Issue Pages 2173-2183  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos A1996UD88400009 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 2.346 Times cited 10 Open Access  
  Notes Approved  
  Call Number UA @ lucian @ c:irua:15799 Serial 2661  
Permanent link to this record
 

 
Author (up) da Costa; Zarenia, M.; Chaves, A.; Pereira, J.M., Jr.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Hexagonal-shaped monolayer-bilayer quantum disks in graphene : a tight-binding approach Type A1 Journal article
  Year 2016 Publication 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 (up) da Silva, A.L.C.; Candido, L.; Teixeira Rabelo, J.N.; Hai, G.-Q.; Peeters, F.M. pdf  doi
openurl 
  Title Anharmonic effects on thermodynamic properties of a graphene monolayer Type A1 Journal article
  Year 2014 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett  
  Volume 107 Issue 5 Pages 56004  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We extend the unsymmetrized self-consistent-field method (USF) for anharmonic crystals to layered non-Bravais crystals to investigate structural, dynamical and thermodynamic properties of a free-standing graphene monolayer. In this theory, the main anharmonicity of the crystal lattice has been included and the quantum corrections are taken into account in an h-expansion for the one-particle density matrix. The obtained result for the thermal expansion coefficient (TEC) of graphene shows a strong temperature dependence and agrees with experimental results by Bao et al. (Nat. Nanotechnol., 4 (2009) 562). The obtained value of TEC at room temperature (300 K) is -6.4 x 10(- 6) K- 1 and it becomes positive for T > T-alpha = 358K. We find that quantum effects are significant for T < 1000 K. The interatomic distance, effective amplitudes of the graphene lattice vibrations, adiabatic and isothermal bulk moduli, isobaric and isochoric heat capacities are also calculated and their temperature dependences are determined. Copyright (C) EPLA, 2014  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Paris Editor  
  Language Wos 000341559900020 Publication Date 2014-09-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0295-5075;1286-4854; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.957 Times cited 23 Open Access  
  Notes ; This research was supported by the Brazilian agencies CNPq, FAPEG and FAPESP, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 1.957; 2014 IF: 2.095  
  Call Number UA @ lucian @ c:irua:119289 Serial 118  
Permanent link to this record
 

 
Author (up) da Silva, R.M.; Milošević, M.V.; Dominguez, D.; Peeters, F.M.; Albino Aguiar, J. doi  openurl
  Title Distinct magnetic signatures of fractional vortex configurations in multiband superconductors Type A1 Journal article
  Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 105 Issue 23 Pages 232601  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Vortices carrying fractions of a flux quantum are predicted to exist in multiband superconductors, where vortex core can split between multiple band-specific components of the superconducting condensate. Using the two-component Ginzburg-Landau model, we examine such vortex configurations in a two-band superconducting slab in parallel magnetic field. The fractional vortices appear due to the band-selective vortex penetration caused by different thresholds for vortex entry within each band-condensate, and stabilize near the edges of the sample. We show that the resulting fractional vortex configurations leave distinct fingerprints in the static measurements of the magnetization, as well as in ac dynamic measurements of the magnetic susceptibility, both of which can be readily used for the detection of these fascinating vortex states in several existing multiband superconductors. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000346266000066 Publication Date 2014-12-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 22 Open Access  
  Notes ; This work was supported by the Brazilian science agencies CAPES (Grant No. PNPD 223038.003145/2011-00), CNPq (Grant Nos. 307552/2012-8, 141911/2012-3, and APV-4 02937/2013-9), and FACEPE (Grant Nos. APQ-0202-1.05/10 and BCT-0278-1.05/ 11), the Research Foundation Flanders (FWO-Vlaanderen), and by the CNPq-FWO cooperation programme (CNPq Grant No. 490297/2009-9). D.D. acknowledges support from CONICET, CNEA, and ANPCyT-PICT2011-1537. The authors thank A. A. Shanenko for extensive discussions on the topic. ; Approved Most recent IF: 3.411; 2014 IF: 3.302  
  Call Number UA @ lucian @ c:irua:122775 Serial 742  
Permanent link to this record
 

 
Author (up) da Silva, R.M.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M.; Albino Aguiar, J. url  doi
openurl 
  Title Giant paramagnetic Meissner effect in multiband superconductors Type A1 Journal article
  Year 2015 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 5 Issue 5 Pages 12695  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Superconductors, ideally diamagnetic when in the Meissner state, can also exhibit paramagnetic behavior due to trapped magnetic flux. In the absence of pinning such paramagnetic response is weak, and ceases with increasing sample thickness. Here we show that in multiband superconductors paramagnetic response can be observed even in slab geometries, and can be far larger than any previous estimate – even multiply larger than the diamagnetic Meissner response for the same applied magnetic field. We link the appearance of this giant paramagnetic response to the broad crossover between conventional Type-I and Type-II superconductors, where Abrikosov vortices interact non-monotonically and multibody effects become important, causing unique flux configurations and their locking in the presence of surfaces.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000359143700001 Publication Date 2015-08-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 25 Open Access  
  Notes ; This work was supported by the Brazilian science agencies CAPES (PNPD 223038.003145/2011-00), CNPq (307552/2012-8, 141911/2012-3, and APV-4 02937/ 2013-9), and FACEPE (APQ-0202-1.05/10 and BCT-0278-1.05/11), the Flemish Science Foundation (FWO-Vl), and by the CNPq-FWO cooperation programme (CNPq 490297/2009-9). R.M.S. acknowledges support from the SRS PhD+ program of the University Cooperation for Development of the Flemish Interuniversity Council (VLIR-UOS). M.V.M. acknowledges support from CNPq (APV-4 02937/2013-9), FACEPE (APV-0034-1.05/14), and CAPES (BEX1392/11-5). ; Approved Most recent IF: 4.259; 2015 IF: 5.578  
  Call Number c:irua:127212 Serial 1339  
Permanent link to this record
 

 
Author (up) Dantas, D.S.; Chaves, A.; Farias, G.A.; Ramos, A.C.A.; Peeters, F.M. pdf  doi
openurl 
  Title Low-dimensional confining structures on the surface of helium films suspended on designed cavities Type A1 Journal article
  Year 2013 Publication 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  
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Author (up) de Aquino, B.R.C.H.T.; Cabral, L.R.E.; de Souza Silva, C.C.; Albino Aguiar, J.; Milošević, M.V.; Peeters, F.M. pdf  doi
openurl 
  Title Dynamic phases of vortex-antivortex molecules in a Corbino disk with magnetic dipole on top Type A1 Journal article
  Year 2012 Publication Physica: C : superconductivity Abbreviated Journal Physica C  
  Volume 479 Issue Pages 115-118  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We performed a molecular dynamics study of vortex-antivortex motion in a superconducting disk with a magnetic dot on top, in the Corbino disk geometry. In this system, vortices and antivortices are forced to move in opposite azimuthal directions by a radially applied current. The dot is magnetized out of plane in order to stabilize composite vortex-antivortex configurations, with vortices closer to the center of the disk and antivortices near to the disk edge. We observe that the interplay between the spatially inhomogeneous current distribution, the screening currents induced by the dipole, and the attractive vortex-antivortex (v-av) interaction result in different dynamical phases. At low current values, antivortices which are distributed at outer rings – remain bounded to vortices at inner rings and the whole configuration rotates rigidly. Above a threshold current, vortices and antivortices unbind and move at different angular velocities in a highly correlated way. Finally, at very strong drive, vortex-antivortex attraction is overhelmed by the external current Lorentz force, causing them to move in opposite directions. (C) 2011 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-4534 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.404 Times cited Open Access  
  Notes Approved Most recent IF: 1.404; 2012 IF: 0.718  
  Call Number UA @ lucian @ c:irua:101870 Serial 764  
Permanent link to this record
 

 
Author (up) de Aquino, B.R.H.; Ghorbanfekr-Kalashami, H.; Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Electrostrictive behavior of confined water subjected to GPa pressure Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 97 Issue 14 Pages 144111  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Water inside a nanocapillary exhibits unconventional structural and dynamical behavior due to its ordered structure. The confining walls, density, and lateral pressures control profoundly the microscopic structure of trapped water. Here we study the electrostriction of confined water subjected to pressures of the order of GPa for two different setups: (i) a graphene nanochannel containing a constant number of water molecules independent of the height of the channel, (ii) an open nanochannel where water molecules can be exchanged with those in a reservoir. For the former case, a square-rhombic structure of confined water is formed when the height of the channel is d = 6.5 angstrom having a density of rho = 1.42 g cm(-3). By increasing the height of the channel, a transition from a flat to a buckled state occurs, whereas the density rapidly decreases and reaches the bulk density for d congruent to 8.5 angstrom. When a perpendicular electric field is applied, the water structure and the lateral pressure change. For strong electric fields (similar to 1 V/angstrom), the square-rhombic structure is destroyed. For an open setup, a solid phase of confined water consisting of an imperfect square-rhombic structure is formed. By applying a perpendicular field, the density and phase of confined water change. However, the density and pressure inside the channel decrease as compared to the first setup. Our study is closely related to recent experiments on confined water, and it reveals the sensitivity of the microscopic structure of confined water to the size of the channel, the external electric field, and the experimental setup.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000430809300002 Publication Date 2018-04-25  
  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 6 Open Access  
  Notes ; This work was supported by the Fund for Scientific Research-Flanders (FWO-Vl) and the Methusalem programe. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:151574UA @ admin @ c:irua:151574 Serial 5023  
Permanent link to this record
 

 
Author (up) de Aquino, B.R.H.; Ghorbanfekr-Kalashami, H.; Neek-Amal, M.; Peeters, F.M. pdf  doi
openurl 
  Title Ionized water confined in graphene nanochannels Type A1 Journal article
  Year 2019 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 21 Issue 18 Pages 9285-9295  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract When confined between graphene layers, water behaves differently from the bulk and exhibits unusual properties such as fast water flow and ordering into a crystal. The hydrogen-bonded network is affected by the limited space and by the characteristics of the confining walls. The presence of an extraordinary number of hydronium and hydroxide ions in narrow channels has the following effects: (i) they affect water permeation through the channel, (ii) they may interact with functional groups on the graphene oxide surface and on the edges, and (iii) they change the thermochemistry of water, which are fundamentally important to understand, especially when confined water is subjected to an external electric field. Here we study the physical properties of water when confined between two graphene sheets and containing hydronium and hydroxide. We found that: (i) there is a disruption in the solvation structure of the ions, which is also affected by the layered structure of confined water, (ii) hydronium and hydroxide occupy specific regions inside the nanochannel, with a prevalence of hydronium (hydroxide) ions at the edges (interior), and (iii) ions recombine more slowly in confined systems than in bulk water, with the recombination process depending on the channel height and commensurability between the size of the molecules and the nanochannel height – a decay of 20% (40%) in the number of ions in 8 ps is observed for a channel height of h = 7 angstrom (bulk water). Our work reveals distinctive properties of water confined in a nanocapillary in the presence of additional hydronium and hydroxide ions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000472922500028 Publication Date 2019-03-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 9 Open Access  
  Notes ; This work was supported by the Fund for Scientific Research Flanders (FWO-Vl) and the Methusalem programe. ; Approved Most recent IF: 4.123  
  Call Number UA @ admin @ c:irua:161377 Serial 5419  
Permanent link to this record
 

 
Author (up) de Araujo, J.L.B.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.; Ferreira, W.P. url  doi
openurl 
  Title Structure and reentrant percolation in an inverse patchy colloidal system Type A1 Journal article
  Year 2017 Publication 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  
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