toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Klimin, S.N.; Tempere, J.; Verhelst, N.; Milošević, M.V. url  doi
openurl 
  Title Finite-temperature vortices in a rotating Fermi gas Type A1 Journal article
  Year 2016 Publication Physical review A Abbreviated Journal Phys Rev A  
  Volume 94 Issue 94 Pages 023620  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract Vortices and vortex arrays have been used as a hallmark of superfluidity in rotated, ultracold Fermi gases. These superfluids can be described in terms of an effective field theory for a macroscopic wave function representing the field of condensed pairs, analogous to the Ginzburg-Landau theory for superconductors. Here we establish how rotation modifies this effective field theory, by rederiving it starting from the action of Fermi gas in the rotating frame of reference. The rotation leads to the appearance of an effective vector potential, and the coupling strength of this vector potential to the macroscopic wave function depends on the interaction strength between the fermions, due to a renormalization of the pair effective mass in the effective field theory. The mass renormalization derived here is in agreement with results of functional renormalization-group theory. In the extreme Bose-Einstein condensate regime, the pair effective mass tends to twice the fermion mass, in agreement with the physical picture of a weakly interacting Bose gas of molecular pairs. Then we use our macroscopic-wave-function description to study vortices and the critical rotation frequencies to form them. Equilibrium vortex state diagrams are derived and they are in good agreement with available results of the Bogoliubov-de Gennes theory and with experimental data.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y. Editor  
  Language Wos 000381473100001 Publication Date 2016-08-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9934 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 6 Open Access  
  Notes (up) ; We are grateful to G. C. Strinati and H. Warringa for valuable discussions. This research was supported by the Flemish Research Foundation Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N, by the Scientific Research Network of the Flemish Research Foundation, Grant No. WO.033.09N, and by the Research Fund of the University of Antwerp. ; Approved Most recent IF: 2.925  
  Call Number UA @ lucian @ c:irua:135686 Serial 4304  
Permanent link to this record
 

 
Author Zha, G.-Q.; Peeters, F.M.; Zhou, S.-P. url  doi
openurl 
  Title Vortex-antivortex dynamics in mesoscopic symmetric and asymmetric superconducting loops with an applied ac current Type A1 Journal article
  Year 2014 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett  
  Volume 108 Issue 5 Pages 57001  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In the framework of the time-dependent Ginzburg-Landau formalism, we study the dynamics of vortex-antivortex (V-Av) pairs in mesoscopic symmetric and asymmetric superconducting loops under an applied ac current. In contrast to the case of a constant biasing dc current, the process of the V-Av collision and annihilation is strongly affected by the time-periodic ac signal. As the direction of the applied ac current is reversed, the existed V-Av pair moves backward and then collides with a new created Av-V pair in a symmetric loop. In the presence of an appropriate external magnetic field, a novel sinusoidal-like oscillatory mode of the magnetization curve is observed, and the periodic dynamical process of the V-Av annihilation occurs in both branches of the sample. Moreover, for the asymmetric sample with an off-centered hole the creation point of the V-Av pair shifts away from the center of the sample, and the creation and annihilation dynamics of V-Av pairs turns out to be very different from the symmetric case. Copyright (C) EPLA, 2014  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Paris Editor  
  Language Wos 000346792400027 Publication Date 2014-11-28  
  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 4 Open Access  
  Notes (up) ; We are grateful to GOLIBJON BERDIYOROV for useful discussions. This work was supported by NSF China under Grant Nos. 61371020 and 61271163, by Visiting Scholar Program of Shanghai Municipal Education Commission, by Innovation Program of Shanghai Municipal Education Commission under Grant No. 13YZ006, and by Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.957; 2014 IF: 2.095  
  Call Number UA @ lucian @ c:irua:122800 Serial 3851  
Permanent link to this record
 

 
Author Xu, B.; Milošević, M.V.; Peeters, F.M. url  doi
openurl 
  Title Calorimetric properties of mesoscopic superconducting disks, rings, and cylinders Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 6 Pages 064501,1-064501,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The thermal signatures of superconductivity in mesoscopic disks, rings and cylinders are calculated within the Ginzburg-Landau theory. In an applied perpendicular magnetic field H the heat capacity of mesoscopic samples shows a strong dependence on the realized vortex state; discontinuities are found at the critical field for different vorticities, as well as at the superconducting-to-normal state transition. The same applies to the intermediate state of type-I superconductors. Even the subtle changes in the fluxoid distribution inside the sample leave clear signatures on heat capacity, which is particularly useful for fully three-dimensional samples whose interior is often inaccessible by magnetometry. The heat-capacity jump ΔC(H) at the critical temperature exhibits quasiperiodic modulations as a function of magnetic field. In mesoscopic superconducting rings, these oscillations provide calorimetric verification of the Little-Parks effect.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000274998100091 Publication Date 2010-02-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 17 Open Access  
  Notes (up) ; We are grateful to O. Bourgeois for useful discussions. This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles (IAP) Program-Belgian State-Belgian Science Policy, ESF-JSPS NES program and the ESF-AQDJJ network. ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:81766 Serial 271  
Permanent link to this record
 

 
Author Peelaers, H.; Partoens, B.; Giantomassi, M.; Rangel, T.; Goossens, E.; Rignanese, G.-M.; Gonze, X.; Peeters, F.M. url  doi
openurl 
  Title Convergence of quasiparticle band structures of Si and Ge nanowires in the GW approximation and the validity of scissor shifts Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 83 Issue 4 Pages 045306-045306,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Starting from fully converged density-functional theory calculations, the quasiparticle corrections are calculated for different sized Si and Ge nanowires using the GW approximation. The effectiveness of recently developed techniques in speeding up the convergence of the quasiparticle calculations is demonstrated. The complete quasiparticle band structures are also obtained using an interpolation technique based on maximallylocalized Wannier functions. From the quasiparticle results, we assess the correctness of the commonly applied scissor-shift correction. Dispersion changes are observed, which are also reflected in changes in the effective band masses calculated taking into account quasiparticle corrections.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000286771400004 Publication Date 2011-01-21  
  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 18 Open Access  
  Notes (up) ; We are grateful to Yann Pouillon for valuable technical support with the build system of ABINIT, related to the WANNIER90 library. This work was supported by the Flemish Science Foundation (FWO-Vl) and by the Interuniversity Attraction Poles Program (P6/42)-Belgian State-Belgian Science Policy. X. G. and G.-M. R. acknowledge funding from the EU's 7th Framework Programme through the ETSF I3 e-Infrastructure project (Grant No. 211956), the Communaute francaise de Belgique through the Action de Recherche Concertee 07/12-003 “Nanosystemes hybrides metal-organiques,” and the Wallon Region Project No. 816849 “ European Theoretical Spectroscopy Facility” (WALL ETSF). M. G. acknowledges funding from the FRFC Project No. 2.4.589.09.F. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:86905 Serial 510  
Permanent link to this record
 

 
Author Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Nanoindentation of a circular sheet of bilayer graphene Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 23 Pages 235421,1-235421,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Nanoindentation of bilayer graphene is studied using molecular-dynamics simulations. We compared our simulation results with those from elasticity theory as based on the nonlinear Föppl-Hencky equations with rigid boundary condition. The force-deflection values of bilayer graphene are compared to those of monolayer graphene. Youngs modulus of bilayer graphene is estimated to be 0.8 TPa which is close to the value for graphite. Moreover, an almost flat bilayer membrane at low temperature under central load has a 14% smaller Youngs modulus as compared to the one at room temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000278710800003 Publication Date 2010-06-11  
  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 108 Open Access  
  Notes (up) ; We gratefully acknowledge comments from R. Asgari. M.N.-A. would like to thank the Universiteit of Antwerpen for its hospitality where part of this work was performed. This work was supported by the Flemish science foundation (FWO-V1) and the Belgium Science Policy (IAP). ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83093 Serial 2259  
Permanent link to this record
 

 
Author Mirzakhani, M.; Peeters, F.M.; Zarenia, M. url  doi
openurl 
  Title Circular quantum dots in twisted bilayer graphene Type A1 Journal article
  Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 101 Issue 7 Pages 075413  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Within a tight-binding approach, we investigate the effect of twisting angle on the energy levels of circular bilayer graphene (BLG) quantum dots (QDs) in both the absence and presence of a perpendicular magnetic field. The QDs are defined by an infinite-mass potential, so that the specific edge effects are not present. In the absence of magnetic field (or when the magnetic length is larger than the moire length), we show that the low-energy states in twisted BLG QDs are completely affected by the formation of moire patterns, with a strong localization at AA-stacked regions. When magnetic field increases, the energy gap of an untwisted BLG QD closes with the edge states, localized at the boundaries between the AA- and AB-stacked spots in a twisted BLG QD. Our observation of the spatial localization of the electrons in twisted BLG QDs can be experimentally probed by low-bias scanning tunneling microscopy measurements.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000512772200004 Publication Date 2020-02-13  
  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 13 Open Access  
  Notes (up) ; We gratefully acknowledge discussions with I. Snyman. M.Z. acknowledges support from the U.S. Department of Energy (Office of Science) under Grant No. DE-FG0205ER46203. ; Approved Most recent IF: 3.7; 2020 IF: 3.836  
  Call Number UA @ admin @ c:irua:166493 Serial 6470  
Permanent link to this record
 

 
Author Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.; Volety, K.; Huyberechts, G.; Paul, J. pdf  doi
openurl 
  Title High throughput first-principles calculations of bixbyite oxides for TCO applications Type A1 Journal article
  Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 16 Issue 33 Pages 17724-17733  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We present a high-throughput computing scheme based on density functional theory (DFT) to generate a class of oxides and screen them with the aim of identifying those that might be electronically appropriate for transparent conducting oxide (TCO) applications. The screening criteria used are a minimum band gap to ensure sufficient transparency, a band edge alignment consistent with easy n- or p-type dopability, and a minimum thermodynamic phase stability to be experimentally synthesizable. Following this scheme we screened 23 binary and 1518 ternary bixbyite oxides in order to identify promising candidates, which can then be a subject of an in-depth study. The results for the known TCOs are in good agreement with the reported data in the literature. We suggest a list of several new potential TCOs, including both n- and p-type compounds.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000341064800041 Publication Date 2014-07-07  
  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 23 Open Access  
  Notes (up) ; We gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project (IWT-n 080023), the FWO-Vlaanderen through project G.0150.13 and a GOA fund from the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation and the Flemish Government (EWI Department). ; Approved Most recent IF: 4.123; 2014 IF: 4.493  
  Call Number UA @ lucian @ c:irua:118263 Serial 1469  
Permanent link to this record
 

 
Author Govaerts, K.; Park, K.; De Beule, C.; Partoens, B.; Lamoen, D. url  doi
openurl 
  Title Effect of Bi bilayers on the topological states of Bi2Se3 : a first-principles study Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 90 Issue 15 Pages 155124  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Bi2Se3 is a three-dimensional topological insulator which has been extensively studied because it has a single Dirac cone on the surface, inside a relatively large bulk band gap. However, the effect of two-dimensional topological insulator Bi bilayers on the properties of Bi2Se3 and vice versa, has not been explored much. Bi bilayers are often present between the quintuple layers of Bi2Se3, since (Bi2)n(Bi2Se3)m form stable ground-state structures. Moreover, Bi2Se3 is a good substrate for growing ultrathin Bi bilayers. By first-principles techniques, we first show that there is no preferable surface termination by either Bi or Se. Next, we investigate the electronic structure of Bi bilayers on top of, or inside a Bi2Se3 slab. If the Bi bilayers are on top, we observe a charge transfer to the quintuple layers that increases the binding energy of the surface Dirac cones. The extra states, originating from the Bi bilayers, were declared to form a topological Dirac cone, but here we show that these are ordinary Rashba-split states. This result, together with the appearance of a new Dirac cone that is localized slightly deeper, might necessitate the reinterpretation of several experimental results. When the Bi bilayers are located inside the Bi2Se3 slab, they tend to split the slab into two topological insulators with clear surface states. Interface states can also be observed, but an energy gap persists because of strong coupling between the neighboring quintuple layers and the Bi bilayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000343773200001 Publication Date 2014-10-20  
  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 30 Open Access  
  Notes (up) ; We gratefully acknowledge financial support from the Research Foundation – Flanders (FWO-Vlaanderen). K.G. thanks the University of Antwerp for a Ph.D. fellowship. C.D.B. is an aspirant of the Flemish Science Foundation. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules Foundation and the Flemish Government (EWI Department). K.P. was supported by U.S. National Science Foundation Grant No. DMR-1206354. ; Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:119527 Serial 800  
Permanent link to this record
 

 
Author Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D. pdf  url
doi  openurl
  Title Native point defects in CuIn1-xGaxSe2 : hybrid density functional calculations predict the origin of p- and n-type conductivity Type A1 Journal article
  Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 16 Issue 40 Pages 22299-22308  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We have performed a first-principles study of the p- and n-type conductivity in CuIn1−xGaxSe2 due to native point defects, based on the HSE06 hybrid functional. Band alignment shows that the band gap becomes larger with x due to the increasing conduction band minimum, rendering it hard to establish n-type conductivity in CuGaSe2. From the defect formation energies, we find that In/GaCu is a shallow donor, while VCu, VIn/Ga and CuIn/Ga act as shallow acceptors. Using the total charge neutrality of ionized defects and intrinsic charge carriers to determine the Fermi level, we show that under In-rich growth conditions InCu causes strongly n-type conductivity in CuInSe2. Under increasingly In-poor growth conditions, the conductivity type in CuInSe2 alters to p-type and compensation of the acceptors by InCu reduces, as also observed in photoluminescence experiments. In CuGaSe2, the native acceptors pin the Fermi level far away from the conduction band minimum, thus inhibiting n-type conductivity. On the other hand, CuGaSe2 shows strong p-type conductivity under a wide range of Ga-poor growth conditions. Maximal p-type conductivity in CuIn1−xGaxSe2 is reached under In/Ga-poor growth conditions, in agreement with charge concentration measurements on samples with In/Ga-poor stoichiometry, and is primarily due to the dominant acceptor CuIn/Ga.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000343072800042 Publication Date 2014-09-05  
  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 43 Open Access  
  Notes (up) ; We gratefully acknowledge financial support from the science fund FWO-Flanders through project G.0150.13. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules foundation and the Flemish Government (EWI Department). We also like to thank Prof. S. Siebentritt of the University of Luxembourg for a presentation of her work on GIGS during a visit to our research group and for helpful discussions of our results. ; Approved Most recent IF: 4.123; 2014 IF: 4.493  
  Call Number UA @ lucian @ c:irua:120465 Serial 2284  
Permanent link to this record
 

 
Author Fatima; Oguz, I.C.; Çakir, D.; Hossain, S.; Mohottige, R.; Gulseren, O.; Oncel, N. url  doi
openurl 
  Title On the structural and electronic properties of Ir-silicide nanowires on Si(001) surface Type A1 Journal article
  Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 120 Issue 120 Pages 095303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Iridium (Ir) modified Silicon (Si) (001) surface is studied with Scanning Tunneling Microscopy/Spectroscopy (STM/STS) and Density Functional Theory (DFT). A model for Ir-silicide nanowires based on STM images and ab-initio calculations is proposed. According to our model, the Ir adatom is on the top of the substrate dimer row and directly binds to the dimer atoms. I-V curves measured at 77K shows that the nanowires are metallic. DFT calculations confirm strong metallic nature of the nanowires. Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000383978100030 Publication Date 2016-09-01  
  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 (up) ; We gratefully acknowledge the NSF (Grant No. DMR-1306101) for financial support. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ; Approved Most recent IF: 2.068  
  Call Number UA @ lucian @ c:irua:137132 Serial 4359  
Permanent link to this record
 

 
Author Nicholls, D.; Li, R.R.; Ware, B.; Pansegrau, C.; Çakir, D.; Hoffmann, M.R.; Oncel, N. doi  openurl
  Title Scanning tunneling microscopy and density functional theory study on zinc(II)-phthalocyanine tetrasulfonic acid on bilayer epitaxial graphene on silicon carbide(0001) Type A1 Journal article
  Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 119 Issue 119 Pages 9845-9850  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Zinc(II)-phthalocyanine tetrasulfonic acid (Zn-PcS) molecules physisorbed on bilayer epitaxial graphene on silicon carbide (SiC(0001)) were studied by using scanning tunneling microscopy/spectroscopy (STM/STS) and density functional theory (DFT). Two different methods were used to deposit Zn-PcS molecules and regardless of the method being used, the surface coverage stayed very low indicating the weakness of surface-molecule interaction. STS measurements revealed that derivative of tunneling current with respect to voltage (dI/dV) measured on Zn-PcS molecules did not exhibit the characteristic dip observed on dI/dV curves of pristine bilayer epitaxial graphene. DFT calculations show that the energy of the lowest unoccupied molecular orbital (LUMO) of the Zn-PcS molecule is below the Dirac point of graphene which enhances local density of states (LDOS). We attribute the disappearance of the dip in the dI/dV curves measured on the Zn-PcS/bilayer system to the LUMO of Zn-PcS. Charge density calculations along Zn-PcS/graphene interface reveal that there is a small charge transfer from graphene to the molecule. Calculated adsorption energy (3.13 eV) of the molecule is notably low and is consistent with the observed low surface coverage at room temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000354339000020 Publication Date 2015-04-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 3 Open Access  
  Notes (up) ; We gratefully acknowledge the NSF (Grant Nos.: DMR-1306101, EPS-814442, and EPS-1354366) for financial support. ; Approved Most recent IF: 4.536; 2015 IF: 4.772  
  Call Number c:irua:126370 Serial 2947  
Permanent link to this record
 

 
Author Varley, J.B.; Peelaers, H.; Janotti, A.; van de Walle, C.G. pdf  doi
openurl 
  Title Hydrogenated cation vacancies in semiconducting oxides Type A1 Journal article
  Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 23 Issue 33 Pages 334212,1-334212,9  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations we have studied the electronic and structural properties of cation vacancies and their complexes with hydrogen impurities in SnO2, In2O3 and β-Ga2O3. We find that cation vacancies have high formation energies in SnO2 and In2O3 even in the most favorable conditions. Their formation energies are significantly lower in β-Ga2O3. Cation vacancies, which are compensating acceptors, strongly interact with H impurities resulting in complexes with low formation energies and large binding energies, stable up to temperatures over 730 °C. Our results indicate that hydrogen has beneficial effects on the conductivity of transparent conducting oxides: it increases the carrier concentration by acting as a donor in the form of isolated interstitials, and by passivating compensating acceptors such as cation vacancies; in addition, it potentially enhances carrier mobility by reducing the charge of negatively charged scattering centers. We have also computed vibrational frequencies associated with the isolated and complexed hydrogen, to aid in the microscopic identification of centers observed by vibrational spectroscopy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000294060600014 Publication Date 2011-08-04  
  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 125 Open Access  
  Notes (up) ; We gratefully acknowledge useful discussions with M D Mc-Cluskey, O Bierwagen and J Speck. The work was supported by the NSF MRSEC Program (DMR05-20415), the Flemish Science Foundation (FWO-VI), the Belgian American Educational Foundation, and by Saint-Gobain Research, and made use of computing facilities at CNSI (NSF grant No. CHE-0321368), TeraGrid and TACC (NSF grant No. DMR070072N), and NERSC (DOE Office of Science Contract No. DE-AC02-05CH11231). ; Approved Most recent IF: 2.649; 2011 IF: 2.546  
  Call Number UA @ lucian @ c:irua:92415 Serial 1534  
Permanent link to this record
 

 
Author Payette, C.; Amaha, S.; Yu, G.; Gupta, J.A.; Austing, D.G.; Nair, S.V.; Partoens, B.; Tarucha, S. url  doi
openurl 
  Title Coherent level mixing in dot energy spectra measured by magnetoresonant tunneling spectroscopy of vertical quantum dot molecules Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 24 Pages 245310,1-245310,15  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study by magnetoresonant tunneling spectroscopy single-particle energy spectra of the constituent weakly coupled dots in vertical quantum dot molecules over a wide energy window. The measured energy spectra are well modeled by calculated spectra for dots with in-plane confinement potentials that are elliptical and parabolic in form. However, in the regions where two, three, or four single-particle energy levels are naively expected to cross, we observe pronounced level anticrossing behavior and strong variations in the resonant currents as a consequence of coherent mixing induced by small deviations in the nearly ideal dot confinement potentials. We present detailed analysis of the energy spectra, and focus on two examples of three-level crossings whereby the coherent mixing leads to concurrent suppression and enhancement of the resonant currents when the anticrossing levels are minimally separated. The suppression of resonant current is of particular interest since it is a signature of dark state formation due to destructive interference. We also describe in detail and compare two measurement strategies to reliably extract the resonant currents required to characterize the level mixing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000278606100003 Publication Date 2010-06-10  
  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 6 Open Access  
  Notes (up) ; We thank A. Bezinger, D. Roth, and M. Malloy for assistance with some of the processing, and K. Ono, T. Kodera, T. Hatano, Y. Tokura, M. Stopa, M. Hilke, G.C. Aers, M. Korkusinski, and R. M. Abolfath for useful discussions. Part of this work is supported by NSERC (Discovery Grant No. 208201), Flemish Science Foundation (FWO-VI), Grant-in-Aid for Scientific Research S (Grant No. 191040070), B (Grant No. 18340081), and by Special Coordination Funds for Promoting Science and Technology, and MEXT. S.T. acknowledges support from QuEST program (BAA-0824). ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:83095 Serial 379  
Permanent link to this record
 

 
Author Costamagna, S.; Neek-Amal, M.; Los, J.H.; Peeters, F.M. url  doi
openurl 
  Title Thermal rippling behavior of graphane Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 86 Issue 4 Pages 041408-4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Thermal fluctuations of single layer hydrogenated graphene (graphane) are investigated using large scale atomistic simulations. By analyzing the mean square value of the height fluctuations < h(2)> and the height-height correlation function H(q) for different system sizes and temperatures, we show that hydrogenated graphene is an unrippled system in contrast to graphene. The height fluctuations are bounded, which is confirmed by a H(q) tending to a constant in the long wavelength limit instead of showing the characteristic scaling law q(4-eta)(eta similar or equal to 0.85) predicted by membrane theory. This unexpected behavior persists up to temperatures of at least 900 K and is a consequence of the fact that in graphane the thermal energy can be accommodated by in-plane bending modes, i.e., modes involving C-C-C bond angles in the buckled carbon layer, instead of leading to significant out-of-plane fluctuations that occur in graphene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000306649200002 Publication Date 2012-07-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 46 Open Access  
  Notes (up) ; We thank A. Fasolino, A. Dobry, and K. H. Michel for their useful comments. S.C. is supported by the Belgian Science Foundation (BELSPO). This work is supported by the ESF-EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:100840 Serial 3630  
Permanent link to this record
 

 
Author Neek-Amal, M.; Beheshtian, J.; Shayeganfar, F.; Singh, S.K.; Los, J.H.; Peeters, F.M. url  doi
openurl 
  Title Spiral graphone and one-sided fluorographene nanoribbons Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 87 Issue 7 Pages 075448-8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The instability of a free-standing one-sided hydrogenated/fluorinated graphene nanoribbon, i.e., graphone/fluorographene, is studied using ab initio, semiempirical, and large-scale molecular dynamics simulations. Free-standing semi-infinite armchairlike hydrogenated/fluorinated graphene (AC-GH/AC-GF) and boatlike hydrogenated/fluorinated graphene (B-GH/B-GF) (nanoribbons which are periodic along the zigzag direction) are unstable and spontaneously transform into spiral structures. We find that rolled, spiral B-GH and B-GF are energetically more favorable than spiral AC-GH and AC-GF which is opposite to the double-sided flat hydrogenated/fluorinated graphene, i.e., graphane/fluorographene. We found that the packed, spiral structures exhibit an unexpected localized highest occupied molecular orbital and lowest occupied molecular orbital at the edges with increasing energy gap during rolling. These rolled hydrocarbon structures are stable beyond room temperature up to at least T = 1000 K within our simulation time of 1 ns. DOI: 10.1103/PhysRevB.87.075448  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000315481800005 Publication Date 2013-02-27  
  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 (up) ; We thank A. Sadeghi, M. R. Ejtehadi, and J. Amini for their useful comments. This work is supported by the ESF EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). M.N.-A. is supported by a EU-Marie Curie IIF fellowship program Grant No. 299855. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:107654 Serial 3106  
Permanent link to this record
 

 
Author Saniz, R.; Vercauteren, S.; Lamoen, D.; Partoens, B.; Barbiellini, B. pdf  doi
openurl 
  Title Accurate description of the van der Waals interaction of an electron-positron pair with the surface of a topological insulator Type P1 Proceeding
  Year 2014 Publication Journal of physics : conference series Abbreviated Journal  
  Volume 505 Issue Pages 012002  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Positrons can be trapped in localized states at the surface of a material, and thus quite selectively interact with core or valence surface electrons. Hence, advanced surface positron spectroscopy techniques can present the ideal tools to study a topological insulator, where surface states play a fundamental role. We analyze the problem of a positron at a TI surface, assuming that it is a weakly physisorbed positronium (Ps) atom. To determine if the surface of interest in a material can sustain such a physisorption, an accurate description of the underlying van der Waals (vdW) interaction is essential. We have developed a first-principles parameterfree method, based on the density functional theory, to extract key parameters determining the vdW interaction potential between a Ps atom and the surface of a given material. The method has been successfully applied to quartz and preliminary results on Bi2Te2Se indicate the existence of a positron surface state. We discuss the robustness of our predictions versus the most relevant approximations involved in our approach.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000338216500002 Publication Date 2014-04-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access  
  Notes (up) ; We thank A. Weiss for very useful conversations. We acknowledge financial support from FWO-Vlaanderen (projectG.0150.13). This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), adivision of the Flemish Supercomputer Center (VSC), funded by the Hercules foundation and the Flemish Government (EWI Department). B. B. is supported by DOE grants Nos. DE-FG02-07ER46352 and DE-AC02-05CH11231 for theory support at ALS, Berkeley, and a NERSC computer time allocation. ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:118264 Serial 46  
Permanent link to this record
 

 
Author Klimin, S.N.; Tempère, J.; Misko, V.R.; Wouters, M. doi  openurl
  Title Finite-temperature Wigner solid and other phases of ripplonic polarons on a helium film Type A1 Journal article
  Year 2016 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 89 Issue 89 Pages 172  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract Electrons on liquid helium can form different phases depending on density, and temperature. Also the electron-ripplon coupling strength influences the phase diagram, through the formation of so-called “ripplonic polarons”, that change how electrons are localized, and that shifts the transition between the Wigner solid and the liquid phase. We use an all-coupling, finite-temperature variational method to study the formation of a ripplopolaron Wigner solid on a liquid helium film for different regimes of the electron-ripplon coupling strength. In addition to the three known phases of the ripplopolaron system (electron Wigner solid, polaron Wigner solid, and electron fluid), we define and identify a fourth distinct phase, the ripplopolaron liquid. We analyse the transitions between these four phases and calculate the corresponding phase diagrams. This reveals a reentrant melting of the electron solid as a function of temperature. The calculated regions of existence of the Wigner solid are in agreement with recent experimental data.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000391225200001 Publication Date 2016-07-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 1 Open Access  
  Notes (up) ; We thank A.S. Mishchenko and D.G. Rees for valuable discussions. This research has been supported by the Flemish Research Foundation (FWO-Vl), Project Nos. G.0115.12N, G.0119.12N, G.0122.12N, G.0429.15N, by the Scientific Research Network of the Research Foundation-Flanders, WO.033.09N, and by the Research Fund of the University of Antwerp. ; Approved Most recent IF: 1.461  
  Call Number UA @ lucian @ c:irua:140351 Serial 4454  
Permanent link to this record
 

 
Author Zarenia, M.; Neilson, D.; Peeters, F.M. url  doi
openurl 
  Title Inhomogeneous phases in coupled electron-hole bilayer graphene sheets : charge density waves and coupled wigner crystals Type A1 Journal article
  Year 2017 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 7 Issue Pages 11510  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Recently proposed accurate correlation energies are used to determine the phase diagram of strongly coupled electron-hole graphene bilayers. The control parameters of the phase diagram are the charge carrier density and the insulating barrier thickness separating the bilayers. In addition to the electron-hole superfluid phase we find two new inhomogeneous ground states, a one dimensional charge density wave phase and a coupled electron-hole Wigner crystal. The elementary crystal structure of bilayer graphene plays no role in generating these new quantum phases, which are completely determined by the electrons and holes interacting through the Coulomb interaction. The experimental parameters for the new phases lie within attainable ranges and therefore coupled electron-hole bilayer graphene presents itself as an experimental system where novel emergent many-body phases can be realized.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000410739000008 Publication Date 2017-09-11  
  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 13 Open Access  
  Notes (up) ; We thank Alex Hamilton, Bart Partoens, and Andrea Perali for useful discussions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ; Approved Most recent IF: 4.259  
  Call Number UA @ lucian @ c:irua:145620 Serial 4742  
Permanent link to this record
 

 
Author Pinto, N.; Rezvani, S.J.; Perali, A.; Flammia, L.; Milošević, M.V.; Fretto, M.; Cassiago, C.; De Leo, N. doi  openurl
  Title Dimensional crossover and incipient quantum size effects in superconducting niobium nanofilms Type A1 Journal article
  Year 2018 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 8 Issue 8 Pages 4710  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Superconducting and normal state properties of Niobium nanofilms have been systematically investigated as a function of film thickness, on different substrates. The width of the superconductingto- normal transition for all films is remarkably narrow, confirming their high quality. The superconducting critical current density exhibits a pronounced maximum for thickness around 25 nm, marking the 3D-to-2D crossover. The magnetic penetration depth shows a sizeable enhancement for the thinnest films. Additional amplification effects of the superconducting properties have been obtained with sapphire substrates or squeezing the lateral size of the nanofilms. For thickness close to 20 nm we measured a doubled perpendicular critical magnetic field compared to its large thickness value, indicating shortening of the correlation length and the formation of small Cooper pairs. Our data analysis indicates an exciting interplay between quantum-size and proximity effects together with strong-coupling effects and the importance of disorder in the thinnest films, placing these nanofilms close to the BCS-BEC crossover regime.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos 000427588300011 Publication Date 2018-03-12  
  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 37 Open Access  
  Notes (up) ; We thank Antonio Bianconi, Mauro Doria and Vincenzo Lacquaniti for useful discussions. We acknowledge the collaboration with Federica Celegato for AFM analysis and Sara Quercetti for the electrical properties characterization. A. P. and N. P. acknowledge financial support from University of Camerino FAR project CESEMN. We also acknowledge the collaboration within the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions. ; Approved Most recent IF: 4.259  
  Call Number UA @ lucian @ c:irua:150843UA @ admin @ c:irua:150843 Serial 4965  
Permanent link to this record
 

 
Author Michel, K.H.; Costamagna; Peeters, F.M. pdf  doi
openurl 
  Title Theory of thermal expansion in 2D crystals Type A1 Journal article
  Year 2015 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B  
  Volume 252 Issue 252 Pages 2433-2437  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000364690400014 Publication Date 2015-08-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0370-1972 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.674 Times cited 21 Open Access  
  Notes (up) ; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; Approved Most recent IF: 1.674; 2015 IF: 1.489  
  Call Number UA @ lucian @ c:irua:130281 Serial 4264  
Permanent link to this record
 

 
Author Michel, K.H.; Costamagna; Peeters, F.M. url  doi
openurl 
  Title Theory of anharmonic phonons in two-dimensional crystals Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 91 Issue 91 Pages 134302  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Anharmonic effects in an atomic monolayer thin crystal with honeycomb lattice structure are investigated by analytical and numerical lattice dynamical methods. Starting from a semiempirical model for anharmonic couplings of third and fourth orders, we study the in-plane and out-of-plane (flexural) mode components of the generalized wave vector dependent Gruneisen parameters, the thermal tension and the thermal expansion coefficients as a function of temperature and crystal size. From the resonances of the displacement-displacement correlation functions, we obtain the renormalization and decay rate of in-plane and flexural phonons as a function of temperature, wave vector, and crystal size in the classical and in the quantum regime. Quantitative results are presented for graphene. There, we find that the transition temperature T-alpha from negative to positive thermal expansion is lowered with smaller system size. Renormalization of the flexural mode has the opposite effect and leads to values of T-alpha approximate to 300 K for systems of macroscopic size. Extensive numerical analysis throughout the Brillouin zone explores various decay and scattering channels. The relative importance of normal and umklapp processes is investigated. The work is complementary to crystalline membrane theory and computational studies of anharmonic effects in two-dimensional crystals.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000353031000001 Publication Date 2015-04-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 38 Open Access  
  Notes (up) ; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the EuroGRAPHENE project CONGRAN. ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:132512 Serial 4263  
Permanent link to this record
 

 
Author Klimin, S.N.; Tempere, J.; Milošević, M.V. url  doi
openurl 
  Title Diversified vortex phase diagram for a rotating trapped two-band Fermi gas in the BCS-BEC crossover Type A1 Journal article
  Year 2018 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 20 Issue 20 Pages 025010  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract We report the equilibrium vortex phase diagram of a rotating two-band Fermi gas confined to a cylindrically symmetric parabolic trapping potential, using the recently developed finite-temperature effective field theory (Klimin et al 2016 Phys. Rev. A 94 023620). A non-monotonic resonant dependence of the free energy as a function of the temperature and the rotation frequency is revealed for a two-band superfluid. We particularly focus on novel features that appear as a result of interband interactions and can be experimentally resolved. The resonant dependence of the free energy is directly manifested in vortex phase diagrams, where areas of stability for both integer and fractional vortex states are found. The study embraces the BCS-BEC crossover regime and the entire temperature range below the critical temperature T-c. Significantly different behavior of vortex matter as a function of the interband coupling is revealed in the BCS and BEC regimes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000426002900001 Publication Date 2018-02-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 6 Open Access  
  Notes (up) ; We thank C A R Sa de Melo and N Verhelst for valuable discussions. This work has been supported by the Research Foundation-Flanders (FWO-Vl), project nrs. G.0115.12N, G.0119.12N, G.0122.12N, G.0429.15N, G.0666.16N, by the Scientific Research Network of the Flemish Research Foundation, WO.033.09N, and by the Research Fund of the University of Antwerp. ; Approved Most recent IF: 3.786  
  Call Number UA @ lucian @ c:irua:149909UA @ admin @ c:irua:149909 Serial 4930  
Permanent link to this record
 

 
Author Becker, T.; Nelissen, K.; Cleuren, B. pdf  doi
openurl 
  Title Current fluctuations in boundary driven diffusive systems in different dimensions : a numerical study Type A1 Journal article
  Year 2015 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 17 Issue 17 Pages 055023  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We use kinetic Monte Carlo simulations to investigate current fluctuations in boundary driven generalized exclusion processes, in different dimensions. Simulation results are in full agreement with predictions based on the additivity principle and the macroscopic fluctuation theory. The current statistics are independent of the shape of the contacts with the reservoirs, provided they are macroscopic in size. In general, the current distribution depends on the spatial dimension. For the special cases of the symmetric simple exclusion process and the zero-range process, the current statistics are the same for all spatial dimensions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000355282700001 Publication Date 2015-05-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 5 Open Access  
  Notes (up) ; We thank Christian Van den Broeck for bringing this problem to our attention. We are grateful to Bart Partoens and Carlo Vanderzande for a careful reading of the manuscript. This work was supported by the Flemish Science Foundation (Fonds Wetenschappelijk Onderzoek), Project No. G038811N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; Approved Most recent IF: 3.786; 2015 IF: 3.558  
  Call Number c:irua:126405 Serial 592  
Permanent link to this record
 

 
Author Croitoru, M.D.; Buzdin, A.I. pdf  doi
openurl 
  Title FFLO-wave-vector lock-in effect in quasi-1D superconductors Type A1 Journal article
  Year 2015 Publication Journal of superconductivity and novel magnetism Abbreviated Journal J Supercond Nov Magn  
  Volume 28 Issue 28 Pages 1305-1308  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study the phase transition into the Fulde-Ferrell-Larkin-Ovchinnikov state in high magnetic field in quasi-one dimensional superconductors within the quasi-classical formalism, taking into account the interchain Josephson coupling and the paramagnetic spin splitting. We show that anomalies in the field-direction dependence of the upper critical field when the magnetic field length equals to the FFLO period, previously described in [29], are characterized by the lock-in effect of the FFLO modulation wave vector, which is governed by the magnetic length.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000352085700019 Publication Date 2014-12-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1557-1939;1557-1947; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.18 Times cited 4 Open Access  
  Notes (up) ; We thank D. Jerome for useful discussions. We acknowledge the support by the French ANR program “ElectroVortex” and European NanoSC COST Action MP1201. M.D.C. acknowledges the support by the BELSPO Return to Belgium Grant. ; Approved Most recent IF: 1.18; 2015 IF: 0.909  
  Call Number c:irua:125540 Serial 1187  
Permanent link to this record
 

 
Author Saberi-Pouya, S.; Zarenia, M.; Perali, A.; Vazifehshenas, T.; Peeters, F.M. url  doi
openurl 
  Title High-temperature electron-hole superfluidity with strong anisotropic gaps in double phosphorene monolayers Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 97 Issue 17 Pages 174503  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Excitonic superfluidity in double phosphorene monolayers is investigated using the BCS mean-field equations. Highly anisotropic superfluidity is predicted where we found that the maximum superfluid gap is in the Bose-Einstein condensate (BEC) regime along the armchair direction and in the BCS-BEC crossover regime along the zigzag direction. We estimate the highest Kosterlitz-Thouless transition temperature with maximum value up to similar to 90 K with onset carrier densities as high as 4 x 10(12) cm(-2). This transition temperature is significantly larger than what is found in double electron-hole few-layers graphene. Our results can guide experimental research toward the realization of anisotropic condensate states in electron-hole phosphorene monolayers.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000431986100002 Publication Date 2018-05-02  
  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 17 Open Access  
  Notes (up) ; We thank David Neilson for helpful discussions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government and Iran Ministry of Science, Research and Technology. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:151533UA @ admin @ c:irua:151533 Serial 5028  
Permanent link to this record
 

 
Author Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Electron-phonon bound state in graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 20 Pages 205453-205453,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The fine structure of the Dirac energy spectrum in graphene induced by electron-optical phonon coupling is investigated in the portion of the spectrum near the phonon emission threshold. The derived new dispersion equation in the immediate neighborhood below the threshold corresponds to an electron-phonon bound state. We find that the singular vertex corrections beyond perturbation theory strongly increase the electron-phonon binding energy scale. The predicted enhancement of the effective electron-phonon coupling can be measured using angle-resolved spectroscopy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304649400002 Publication Date 2012-05-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 12 Open Access  
  Notes (up) ; We thank E. Rashba for the useful discussion and acknowledge support from the Belgian Science Policy (IAP) and BELSPO. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98939 Serial 982  
Permanent link to this record
 

 
Author Pina, J.C.; de Souza Silva, C.C.; Milošević, M.V. url  doi
openurl 
  Title Stability of fractional vortex states in a two-band mesoscopic superconductor Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 86 Issue 2 Pages 024512  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate the stability of noncomposite fractional vortex states in a mesoscopic two-band superconductor within the two-component Ginzburg-Landau model. Our analysis explicitly takes into account the relationship between the model parameters and microscopic material parameters, such as partial density of states, Fermi velocities and elements of the electron-phonon coupling matrix. We have found that states with different phase winding number in each band (L-1 not equal L-2) and fractional flux can exist in many different configurations, including rather unconventional ones where the dominating band carries larger winding number and states where vertical bar L-1 – L-2 vertical bar > 1. We present a detailed analysis of the stability of the observed vortex structures with respect to changing the microscopic parameters, showing that, in the weak coupling case, fractional vortex states can be assessed in essentially the whole range of temperatures and applied magnetic fields in which both bands are active. Finally, we propose an efficient way of increasing the range of parameters for which these fractional vortex states can be stabilized. In particular, our proposal allows for observation of fractional vortex structures in materials with stronger coupling, where those states are forbidden at a homogeneous field. This is accomplished with the help of the stray fields of a suitably prepared magnetic dot placed nearby the superconducting disk.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000306309600006 Publication Date 2012-07-14  
  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 38 Open Access  
  Notes (up) ; We thank Eric B. Claude, Miguel A. Zorro, and Rogerio M. da Silva for assistance in the development of the numerical code used in our simulations. This work was supported by the Brazilian science agencies CNPq and FACEPE, by the FACEPE/CNPq-PRONEX program, under Grant No. APQ-0589-1.05/08, and by CNPq-FWO Brazil-Flanders co-operation program. M.V.M. acknowledges support from the CAPES-PVE program. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:100766 Serial 3126  
Permanent link to this record
 

 
Author Moldovan, D.; Masir, M.R.; Peeters, F.M. pdf  url
doi  openurl
  Title Magnetic field dependence of the atomic collapse state in graphene Type A1 Journal article
  Year 2018 Publication 2D materials Abbreviated Journal 2D Mater  
  Volume 5 Issue 1 Pages 015017  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract <script type='text/javascript'>document.write(unpmarked('Quantum electrodynamics predicts that heavy atoms (Z \u003E Z(c) approximate to 170) will undergo the process of atomic collapse where electrons sink into the positron continuum and a new family of so-called collapsing states emerges. The relativistic electrons in graphene exhibit the same physics but at a much lower critical charge (Z(c) approximate to 1) which has made it possible to confirm this phenomenon experimentally. However, there exist conflicting predictions on the effect of a magnetic field on atomic collapse. These theoretical predictions are based on the continuum Dirac-Weyl equation, which does not have an exact analytical solution for the interplay of a supercritical Coulomb potential and the magnetic field. Approximative solutions have been proposed, but because the two effects compete on similar energy scales, the theoretical treatment varies depending on the regime which is being considered. These limitations are overcome here by starting from a tight-binding approach and computing exact numerical results. By avoiding special limit cases, we found a smooth evolution between the different regimes. We predict that the atomic collapse effect persists even after the magnetic field is activated and that the critical charge remains unchanged. We show that the atomic collapse regime is characterized: (1) by a series of Landau level anticrossings and (2) by the absence of root B scaling of the Landau levels with regard to magnetic field strength.'));  
  Address  
  Corporate Author Thesis  
  Publisher IOP Publishing Place of Publication Bristol Editor  
  Language Wos 000415015000001 Publication Date 2017-10-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.937 Times cited 13 Open Access  
  Notes (up) ; We thank Eva Andrei, Jinhai Mao and Yuhang Jiang for insightful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. ; Approved Most recent IF: 6.937  
  Call Number UA @ lucian @ c:irua:147361UA @ admin @ c:irua:147361 Serial 4884  
Permanent link to this record
 

 
Author De Beule, C.; Ziani, N.T.; Zarenia, M.; Partoens, B.; Trauzettel, B. url  doi
openurl 
  Title Correlation and current anomalies in helical quantum dots Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 94 Issue 94 Pages 155111  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We theoretically investigate the ground-state properties of a quantum dot defined on the surface of a strong three-dimensional time-reversal invariant topological insulator. Confinement is realized by ferromagnetic barriers and Coulomb interaction is treated numerically for up to seven electrons in the dot. Experimentally relevant intermediate interaction strengths are considered. The topological origin of the dot has several consequences: (i) spin polarization increases and the ground state exhibits quantum phase transitions at specific angular momenta as a function of interaction strength, (ii) the onset of Wigner correlations takes place mainly in one spin channel, and (iii) the ground state is characterized by a robust persistent current that changes sign as a function of the distance from the center of the dot.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000385242200001 Publication Date 2016-10-07  
  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 3 Open Access  
  Notes (up) ; We thank F. Cavaliere, F. Crepin, C. Felser, and B. Yan for interesting discussions, and S. Curreli for performing the finite-element calculation of the magnetic field in COMSOL. C.D.B. and M.Z. are supported by the Flemish Research Foundation (FWO). N.T.Z. and B.T. acknowledge financial support by the DFG (SPP1666 and SFB1170 “ToCoTronics”), the Helmholtz Foundation (VITI), and the ENB Graduate School on “Topological Insulators.” ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:137234 Serial 4351  
Permanent link to this record
 

 
Author Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Effect of nonhomogenous dielectric background on the plasmon modes in graphene double-layer structures at finite temperatures Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 19 Pages 195444-195444,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We have calculated the plasmon modes in graphene double layer structures at finite temperatures, taking into account the inhomogeneity of the dielectric background of the system. The effective dielectric function is obtained from the solution of the Poisson equation of a three-layer dielectric medium with graphene sheets located at the interfaces, separating the different materials. Due to the momentum dispersion of the effective dielectric function, the intra- and interlayer bare Coulomb interactions in the graphene double layer system acquires an additional momentum dependence-an effect that is of the order of the interlayer interaction itself. We show that the energies of the in-phase and out-of-phase plasmon modes are determined largely by different values of the spatially dependent effective dielectric function. The effect of the dielectric inhomogeneity increases with temperature, and even at high temperatures the energy shift induced by the dielectric inhomogeneity and temperature itself remains larger than the broadening of the plasmon energy dispersions due to the Landau damping. The obtained new features of the plasmon dispersions can be observed in frictional drag measurements and in inelastic light scattering and electron energy-loss spectroscopies.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304394800011 Publication Date 2012-05-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 67 Open Access  
  Notes (up) ; We thank G. Vignale for useful discussions and acknowledge support from the Flemisch Science Foundation (FWO-Fl) and the Belgian Science Policy (BELSPO). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98941 Serial 826  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: