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Author Torun, E.; Sahin, H.; Bacaksiz, C.; Senger, R.T.; Peeters, F.M.
  Title Tuning the magnetic anisotropy in single-layer crystal structures Type A1 Journal article
  Year 2015 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 92 Issue 92 Pages 104407
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The effect of an applied electric field and the effect of charging are investigated on themagnetic anisotropy (MA) of various stable two-dimensional (2D) crystals such as graphene, FeCl2, graphone, fluorographene, and MoTe2 using first-principles calculations. We found that themagnetocrystalline anisotropy energy of Co-on-graphene and Os-doped-MoTe2 systems change linearly with electric field, opening the possibility of electric field tuningMAof these compounds. In addition, charging can rotate the easy-axis direction ofCo-on-graphene andOs-doped-MoTe2 systems from the out-of-plane (in-plane) to in-plane (out-of-plane) direction. The tunable MA of the studied materials is crucial for nanoscale electronic technologies such as data storage and spintronics devices. Our results show that controlling the MA of the mentioned 2D crystal structures can be realized in various ways, and this can lead to the emergence of a wide range of potential applications where the tuning and switching of magnetic functionalities are important.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000360961400004 Publication Date 2015-09-11
  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 37 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish government. 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. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. C.B. and R.T.S. acknowledge support from TUBITAK Project No. 111T318. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
  Call Number UA @ lucian @ c:irua:127838 Serial 4269
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Author Cabral, L.R.E.; de Aquino, B.R.C.H.T.; de Souza Silva, C.C.; Milošević, M.V.; Peeters, F.M.
  Title Two-shell vortex and antivortex dynamics in a Corbino superconducting disk Type A1 Journal article
  Year 2016 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 93 Issue 93 Pages 014515
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We examine theoretically the dynamics of two vortex shells in pinning-free superconducting thin disks in the Corbino geometry. In the first considered case, the inner shell is composed of vortices and the outer one of antivortices, corresponding to a state induced by the stray field of an off-plane magnetic dipole placed on top of the superconductor. In the second considered case, both shells comprise vortices induced by a homogeneous external field. We derive the equation of motion for each shell within the Bardeen-Stephen model and study the dynamics analytically by assuming both shells are rigid and commensurate. In both cases, two distinct regimes for vortex shell motion are identified: For low applied currents the entire configuration rotates rigidly, while above a threshold current the shells decouple from each other and rotate at different angular velocities. Analytical expressions for the decoupling current, the recombination time in the decoupled phases, as well as the voltage-current characteristics are presented. Our analytical results are in excellent agreement with numerical molecular dynamics simulations of the full many-vortex problem.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000368481600003 Publication Date 2016-01-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 7 Open Access
  Notes ; This work was supported by the Brazilian Science Agencies CAPES, CNPq, and FACEPE under Grants No. APQ-1381-1.05/12, No. APQ 2017-1.05/12, and No. APQ-0598/1.05-08 and by EU-COST Action No. MP1201 and the Research Foundation-Flanders (FWO). ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:131541 Serial 4270
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Author Krstajić, P.M.; Van Duppen, B.; Peeters, F.M.
  Title Plasmons and their interaction with electrons in trilayer graphene Type A1 Journal article
  Year 2013 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 88 Issue 19 Pages 195423
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The interaction between electrons and plasmons in trilayer graphene is investigated within the Overhauser approach resulting in the “plasmaron” quasiparticle. This interaction is cast into a field theoretical problem, and its effect on the energy spectrum is calculated using improved Wigner-Brillouin perturbation theory. The plasmaron spectrum is shifted with respect to the bare electron spectrum by ΔE(k)∼150−200meV for ABC stacked trilayer graphene and for ABA trilayer graphene by ΔE(k)∼30−150 meV[ ΔE(k) ∼1 −5meV] for the hyperbolic (linear) part of the spectrum. The shift in general increases with the electron concentration and electron momentum. The dispersion of plasmarons is more pronounced in ABC stacked than in ABA stacked trilayer graphene, because of the different energy band structure and their different plasmon dispersion.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000327239200003 Publication Date 2013-11-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121 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 Flemish Science Foundation (FWO-Vl), by the ESF-EuroGRAPHENE project CON-GRAN, and by the Serbian Ministry of Education and Science, within the Project No. TR 32008. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number CMT @ cmt @ c:irua:112702 Serial 4489
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Author Dzhurakhalov, A.A.; Atanasov, I.; Hou, M.
  Title Calculation of binary and ternary metallic immiscible clusters with icosahedral structures Type A1 Journal article
  Year 2008 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume Issue Pages 115415
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Recently, core-shell Ag-Co, Ag-Cu, and “onionlike” Cu-Co equilibrium configurations were predicted in the case of isolated face centered cubic (fcc) bimetallic clusters, and three shell onionlike configurations were predicted in the case of ternary metallic clusters with spherical and truncated octahedral morphologies. In the present paper, immiscible binary CuCo and ternary AgCuCo clusters with icosahedral structures are studied as functions of their size and composition. Clusters studied are formed by 13, 55, 147, 309, and 561 atoms corresponding to the five smallest possible closed shell icosahedral structures. An embedded atom model potential is used to describe their cohesion. Equilibrium configurations are investigated by means of Metropolis Monte Carlo free energy minimization in the (NPT) canonical ensemble. Most simulations are achieved at 10 and 300 K. The effect of temperature on segregation ordering is systematically investigated. Selected cases are used to identify the effect of size and composition on melting. In contrast with fcc clusters, homogeneous onionlike configurations of binary clusters are not predicted. When it is allowed by the composition, a complete outer shell is formed by Cu in binary Cu-Co clusters and by Ag in ternary Ag-Cu-Co clusters. Depending on temperature, Co may precipitate into decahedral groups under the Cu vertices of the icosahedra in binary clusters, while the Co-Cu configuration in ternary clusters drastically depends on the Ag coating. Despite the multicomponent character of the clusters and the immiscibility of the species forming them, for most compositions and sizes, equilibrium structures remain close to perfectly icosahedral at 10 K as well as at 300 K.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000254542800167 Publication Date 2008-03-11
  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 11 Open Access
  Notes Approved Most recent IF: 3.836; 2008 IF: 3.322
  Call Number UA @ lucian @ c:irua:104033 Serial 4517
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Author Çakir, D.; Otalvaro, D.M.; Brocks, G.
  Title From spin-polarized interfaces to giant magnetoresistance in organic spin valves Type A1 Journal article
  Year 2014 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 89 Issue 11 Pages 115407
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We calculate the spin-polarized electronic transport through a molecular bilayer spin valve from first principles, and establish the link between the magnetoresistance and the spin-dependent interactions at the metal-molecule interfaces. The magnetoresistance of a Fe vertical bar bilayer-C-70 vertical bar Fe spin valve attains a high value of 70% in the linearresponse regime, but it drops sharply as a function of the applied bias. The current polarization has a value of 80% in linear response and also decreases as a function of bias. Both these trends can be modeled in terms of prominent spin-dependent Fe vertical bar C-70 interface states close to the Fermi level, unfolding the potential of spinterface science to control and optimize spin currents.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000332504900007 Publication Date 2014-03-10
  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 14 Open Access
  Notes ; ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:128321 Serial 4596
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Author Gillis, S.; Jaykka, J.; Milošević, M.V.
  Title Vortex states in mesoscopic three-band superconductors Type A1 Journal article
  Year 2014 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 89 Issue 2 Pages 024512
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using multicomponent Ginzburg-Landau simulations, we show a plethora of vortex states possible in mesoscopic three-band superconductors. We find that mesoscopic confinement stabilizes chiral states, with nontrivial phase differences between the band condensates, as the ground state of the system. As a consequence, we report the broken-symmetry vortex states, the chiral states where vortex cores in different band condensates do not coincide (split-core vortices), as well as fractional-flux vortex states with broken time-reversal symmetry.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000333653800001 Publication Date 2014-01-24
  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 26 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO). Critical remarks of Lucia Komendova are gratefully acknowledged. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:128885 Serial 4611
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Author Kukhlevsky, S.V.; Mechler, M.; Csapo, L.; Janssens, K.; Samek, O.
  Title Enhanced transmission versus localization of a light pulse by a subwavelength metal slit Type A1 Journal article
  Year 2004 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 70 Issue 19 Pages 195428,1-9
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000225477800152 Publication Date 2004-11-19
  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 Approved Most recent IF: 3.836; 2004 IF: 3.075
  Call Number UA @ admin @ c:irua:50849 Serial 5604
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Author Kukhlevsky, S.V.; Mechler, M.; Csapó, L.; Janssens, K.; Samek, O.
  Title Resonant backward scattering of light by a subwavelength metallic slit with two open sides Type A1 Journal article
  Year 2005 Publication (down) Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 72 Issue 16 Pages 165421,1-165421,7
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract The backward scattering of TM-polarized light by a two-side-open subwavelength slit in a metal film is analyzed. We show that the reflection coefficient versus wavelength possesses a Fabry-Perot-like dependence that is similar to the anomalous behavior of transmission reported in the study [Y. Takakura, Phys. Rev. Lett. 86, 5601 (2001)]. The open slit totally reflects the light at the near-to-resonance wavelengths. In addition, we show that the interference of incident and resonantly backward-scattered light produces in the near-field diffraction zone a spatially localized wave whose intensity is 10103 times greater than the incident wave, but one order of magnitude smaller than the intracavity intensity. The amplitude and phase of the resonant wave at the slit entrance and exit are different from that of a Fabry-Perot cavity.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000232934900123 Publication Date 2005-10-21
  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 7 Open Access
  Notes Approved Most recent IF: 3.836; 2005 IF: 3.185
  Call Number UA @ admin @ c:irua:71385 Serial 5815
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Author Shanenko, A.A.; Croitoru, M.D.; Vagov, A.V.; Axt, V.M.; Perali, A.; Peeters, F.M.
  Title Atypical BCS-BEC crossover induced by quantum-size effects Type A1 Journal article
  Year 2012 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 86 Issue 3 Pages 033612
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Quantum-size oscillations of the basic physical characteristics of a confined fermionic condensate are a well-known phenomenon. Its conventional understanding is based on the single-particle physics, whereby the oscillations follow variations in the single-particle density of states driven by the size quantization. Here we present a study of a cigar-shaped ultracold superfluid Fermi gas, which demonstrates an important many-body aspect of the quantum-size coherent effects, overlooked previously. The many-body physics is revealed here in the atypical crossover from the Bardeen-Cooper-Schrieffer (BCS) superfluid to the Bose-Einstein condensate (BEC) induced by the size quantization of the particle motion. The single-particle energy spectrum for the transverse dimensions is tightly bound, whereas for the longitudinal direction it resembles a quasi-free dispersion. This results in the formation of a series of single-particle subbands (shells) so that the aggregate fermionic condensate becomes a coherent mixture of subband condensates. Each time when the lower edge of a subband crosses the chemical potential, the BCS-BEC crossover is approached in this subband, and the aggregate condensate contains both BCS and BEC-like components.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y Editor
  Language Wos 000308639500004 Publication Date 2012-09-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 34 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). The authors thank C. Salomon and C. Vale for their valuable explications of the experimental situation and interest to our work. We are grateful to G. C. Strinati, D. Neilson, and P. Pieri for useful discussions. M. D. C. acknowledges support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). A. P. gratefully acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 4844 for his visit to the University of Antwerp. A. A. S. acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 5200 for his visit to the University of Camerino. ; Approved Most recent IF: 2.925; 2012 IF: 3.042
  Call Number UA @ lucian @ c:irua:101844 Serial 203
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Author Dantas, D.S.; Lima, A.R.P.; Chaves, A.; Almeida, C.A.S.; Farias, G.A.; Milošević, M.V.
  Title Bound vortex states and exotic lattices in multicomponent Bose-Einstein condensates : the role of vortex-vortex interaction Type A1 Journal article
  Year 2015 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 91 Issue 91 Pages 023630
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We numerically study the vortex-vortex interaction in multicomponent homogeneous Bose-Einstein condensates within the realm of the Gross-Pitaevskii theory. We provide strong evidence that pairwise vortex interaction captures the underlying mechanisms which determine the geometric configuration of the vortices, such as different lattices in many-vortex states, as well as the bound vortex states with two (dimer) or three (trimer) vortices. Specifically, we discuss and apply our theoretical approach to investigate intra- and intercomponent vortex-vortex interactions in two- and three-component Bose-Einstein condensates, thereby shedding light on the formation of the exotic vortex configurations. These results correlate with current experimental efforts in multicomponent Bose-Einstein condensates and the understanding of the role of vortex interactions in multiband superconductors.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000350255200014 Publication Date 2015-02-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 12 Open Access
  Notes ; This work was supported by the National Council for Scientific and Technological Development (CNPq-Brazil), the Coordination for the Improvement of Higher Education Personnel (CAPES-Brazil), Research Foundation Flanders (FWO), and the bilateral FWO-CNPq program between Flanders and Brazil. M.V.M. acknowledges support from the CAPES-PVE program (Grant No. BEX1392/11-5). ; Approved Most recent IF: 2.925; 2015 IF: 2.808
  Call Number c:irua:124907 Serial 252
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Author Földi, P.; Benedict, M.G.; Peeters, F.M.
  Title Dynamics of periodic anticrossings: decoherence, pointer states, and hysteresis curves Type A1 Journal article
  Year 2008 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 77 Issue 1 Pages 013406,1-10
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000252862000122 Publication Date 2008-01-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 10 Open Access
  Notes Approved Most recent IF: 2.925; 2008 IF: 2.908
  Call Number UA @ lucian @ c:irua:67890 Serial 781
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Author Kuopanportti, P.; Orlova, N.V.; Milošević, M.V.
  Title Ground-state multiquantum vortices in rotating two-species superfluids Type A1 Journal article
  Year 2015 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 91 Issue 91 Pages 043605
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We show numerically that a rotating, harmonically trapped mixture of two Bose-Einstein-condensed superfluids cancontrary to its single-species counterpartcontain a multiply quantized vortex in the ground state of the system. This giant vortex can occur without any accompanying single-quantum vortices, may either be coreless or have an empty core, and can be realized in a Rb87−K41 Bose-Einstein condensate. Our results not only provide a rare example of a stable, solitary multiquantum vortex but also reveal exotic physics stemming from the coexistence of multiple, compositionally distinct condensates in one system.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000352255200005 Publication Date 2015-04-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 25 Open Access
  Notes ; This work was supported by the Finnish Cultural Foundation, the Research Foundation – Flanders (FWO), and the Magnus Ehrnrooth Foundation. We thank E. Ruokokoski and T. P. Simula for valuable comments and discussions. ; Approved Most recent IF: 2.925; 2015 IF: 2.808
  Call Number c:irua:124906 Serial 1388
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Author Matulis, A.; Masir, M.R.; Peeters, F.M.
  Title Scattering of a Dirac electron on a mass barrier Type A1 Journal article
  Year 2012 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 86 Issue 2 Pages 022101
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The interaction of a wave packet (and in particular the wave front) with a mass barrier is investigated in one dimension. We discuss the main features of the wave packet that are inherent to two-dimensional wave packets, such as compression during reflection, penetration in the case when the energy is lower than the height of the barrier, waving tails, precursors, and the retardation of the reflected and penetrated wave packets. These features depend on the wave-packet envelope function which we demonstrate by considering the case of a rectangular wave packet with sharp front and trailing edges and a smooth Gaussian wave packet. The method of Fourier integral for obtaining the nonstationary solutions is used.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000306991200001 Publication Date 2012-08-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 9 Open Access
  Notes ; This research was supported by the Flemish Science Foundation (FWO-Vl) and (in part) by the Lithuanian Science Council under Project No. MIP-79/2010. ; Approved Most recent IF: 2.925; 2012 IF: 3.042
  Call Number UA @ lucian @ c:irua:100822 Serial 2948
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Author Geurts, R.; Milošević, M.V.; Peeters, F.M.
  Title Topologically trapped vortex molecules in Bose-Einstein condensates Type A1 Journal article
  Year 2008 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 78 Issue 5 Pages 053610,1-053610,5
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract In a numerical experiment based on Gross-Pitaevskii formalism, we demonstrate unique topological quantum coherence in optically trapped Bose-Einstein condensates (BECs). Exploring the fact that vortices in a rotating BEC can be pinned by a geometric arrangement of laser beams, we show the parameter range in which vortex-antivortex molecules or multiquantum vortices are formed as a consequence of the optically imposed symmetry. Being low-energy states, we discuss the conditions for spontaneous nucleation of these unique molecules and their direct experimental observation, and provoke the potential use of the phase print of an antivortex or a multiquantum vortex when realized in unconventional circumstances.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000261215600127 Publication Date 2008-11-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 12 Open Access
  Notes Approved Most recent IF: 2.925; 2008 IF: 2.908
  Call Number UA @ lucian @ c:irua:73184 Serial 3679
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Author Hannibal, S.; Kettmann, P.; Croitoru, M.D.; Vagov, A.; Axt, V.M.; Kuhn, T.
  Title Quench dynamics of an ultracold Fermi gas in the BCS regime : spectral properties and confinement-induced breakdown of the Higgs mode Type A1 Journal article
  Year 2015 Publication (down) Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 91 Issue 91 Pages 043630
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The Higgs amplitude mode of the order parameter of an ultracold confined Fermi gas in the BCS regime after a quench of the coupling constant is analyzed theoretically. A characteristic feature is a damped oscillation which at a certain transition time changes into a rather irregular dynamics. We compare the numerical solution of the full set of nonlinear equations of motion for the normal and anomalous Bogoliubov quasiparticle excitations with a linearized approximation. In doing so the transition time as well as the difference between resonant systems, i.e., systems where the Fermi energy is close to a sub-band minimum, and off-resonant systems can be well understood and traced back to the system and geometry parameters.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000353448500005 Publication Date 2015-04-24
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1094-1622; 1050-2947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 10 Open Access
  Notes ; M.D.C. acknowledges support by the BELSPO Back to Belgium Grant. ; Approved Most recent IF: 2.925; 2015 IF: NA
  Call Number UA @ lucian @ c:irua:132509 Serial 4235
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Author Houssa, M.; van den Broek, B.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
  Title An electric field tunable energy band gap at silicene/(0001) ZnS interfaces Type A1 Journal article
  Year 2013 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 15 Issue 11 Pages 3702-3705
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The interaction of silicene, the silicon counterpart of graphene, with (0001) ZnS surfaces is investigated theoretically, using first-principles simulations. The charge transfer occurring at the silicene/(0001) ZnS interface leads to the opening of an indirect energy band gap of about 0.7 eV in silicene. Remarkably, the nature (indirect or direct) and magnitude of the energy band gap of silicene can be controlled by an external electric field: the energy gap is predicted to become direct for electric fields larger than about 0.5 V angstrom(-1), and the direct energy gap decreases approximately linearly with the applied electric field. The predicted electric field tunable energy band gap of the silicene/(0001) ZnS interface is very promising for its potential use in nanoelectronic devices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000315165100002 Publication Date 2013-01-29
  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 74 Open Access
  Notes Approved Most recent IF: 4.123; 2013 IF: 4.198
  Call Number UA @ lucian @ c:irua:107702 Serial 94
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Author Çakir, D.; Sahin, H.; Peeters, F.M.
  Title Doping of rhenium disulfide monolayers : a systematic first principles study Type A1 Journal article
  Year 2014 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 16 Issue 31 Pages 16771-16779
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The absence of a direct-to-indirect band gap transition in ReS2 when going from the monolayer to bulk makes it special among the other semiconducting transition metal dichalcogenides. The functionalization of this promising layered material emerges as a necessity for the next generation technological applications. Here, the structural, electronic, and magnetic properties of substitutionally doped ReS2 monolayers at either the S or Re site were systematically studied by using first principles density functional calculations. We found that substitutional doping of ReS2 depends sensitively on the growth conditions of ReS2. Among the large number of non-metallic atoms, namely H, B, C, Se, Te, F, Br, Cl, As, P. and N, we identified the most promising candidates for n-type and p-type doping of ReS2. While Cl is an ideal candidate for n-type doping, P appears to be the most promising candidate for p-type doping of the ReS2 monolayer. We also investigated the doping of ReS2 with metal atoms, namely Mo, W, Ti, V. Cr, Co, Fe, Mn, Ni, Cu, Nb, Zn, Ru, Os and Pt. Mo, Nb, Ti, and V atoms are found to be easily incorporated in a single layer of ReS2 as substitutional impurities at the Re site for all growth conditions considered in this work. Tuning chemical potentials of dopant atoms energetically makes it possible to dope ReS2 with Fe, Co, Cr, Mn, W, Ru, and Os at the Re site. We observe a robust trend for the magnetic moments when substituting a Re atom with metal atoms such that depending on the electronic configuration of dopant atoms, the net magnetic moment of the doped ReS2 becomes either 0 or 1 mu(B). Among the metallic dopants, Mo is the best candidate for p-type doping of ReS2 owing to its favorable energetics and promising electronic properties.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000340075700048 Publication Date 2014-07-02
  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 58 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI) and the Methusalem foundation of the Flemish government. 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. H.S. is supported by a FWO Pegasus-long Marie Curie Fellowship. D.C. is supported by a FWO Pegasus-short Marie Curie Fellowship. ; Approved Most recent IF: 4.123; 2014 IF: 4.493
  Call Number UA @ lucian @ c:irua:118742 Serial 752
Permanent link to this record
 

 
Author Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
  Title The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels Type A1 Journal article
  Year 2014 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 16 Issue 6 Pages 2588-2596
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000329926700040 Publication Date 2013-12-03
  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 47 Open Access
  Notes Fwo; Goa; Hercules Approved Most recent IF: 4.123; 2014 IF: 4.493
  Call Number UA @ lucian @ c:irua:114829 Serial 2525
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Author Sliem, M.A.; Turner, S.; Heeskens, D.; Kalidindi, S.B.; Van Tendeloo, G.; Muhler, M.; Fischer, R.A.
  Title Preparation, microstructure characterization and catalytic performance of Cu/ZnO and ZnO/Cu composite nanoparticles for liquid phase methanol synthesis Type A1 Journal article
  Year 2012 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 14 Issue 22 Pages 8170-8178
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Stearate@Cu/ZnO nanocomposite particles with molar ratios of ZnO ∶ Cu = 2 and 5 are synthesized by reduction of the metalorganic Cu precursor [Cu{(OCH(CH3)CH2N(CH3)2)}2] in the presence of stearate@ZnO nanoparticles. In the case of ZnO ∶ Cu = 5, high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) combined with electron-energy-loss-spectroscopy (EELS) as well as attenuated total reflection Fourier transform infrared (ATR-IR) spectroscopy are used to localize the small amount of Cu deposited on the surface of 35 nm sized stearate@ZnO particles. For ZnO ∶ Cu = 2, the microstructure of the nanocomposites after catalytic activity testing is characterized by HAADF-STEM techniques. This reveals the construction of large Cu nanoparticles (2050 nm) decorated by small ZnO nanoparticles (35 nm). The catalytic activity of both composites for the synthesis of methanol from syn gas is evaluated.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000304102200033 Publication Date 2012-04-16
  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 16 Open Access
  Notes Fwo Approved Most recent IF: 4.123; 2012 IF: 3.829
  Call Number UA @ lucian @ c:irua:98377 Serial 2702
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Author Çakir, D.; Kecik, D.; Sahin, H.; Durgun, E.; Peeters, F.M.
  Title Realization of a p-n junction in a single layer boron-phosphide Type A1 Journal article
  Year 2015 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 17 Issue 17 Pages 13013-13020
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Two-dimensional (2D) materials have attracted growing interest due to their potential use in the next generation of nanoelectronic and optoelectronic applications. On the basis of first-principles calculations based on density functional theory, we first investigate the electronic and mechanical properties of single layer boron phosphide (h-BP). Our calculations show that h-BP is a mechanically stable 2D material with a direct band gap of 0.9 eV at the K-point, promising for both electronic and optoelectronic applications. We next investigate the electron transport properties of a p-n junction constructed from single layer boron phosphide (h-BP) using the non-equilibrium Green's function formalism. The n-and p-type doping of BP are achieved by substitutional doping of B with C and P with Si, respectively. C(Si) substitutional doping creates donor (acceptor) states close to the conduction (valence) band edge of BP, which are essential to construct an efficient p-n junction. By modifying the structure and doping concentration, it is possible to tune the electronic and transport properties of the p-n junction which exhibits not only diode characteristics with a large current rectification but also negative differential resistance (NDR). The degree of NDR can be easily tuned via device engineering.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000354195300065 Publication Date 2015-04-16
  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 104 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem foundation of the Flemish government and the Bilateral program FWO-TUBITAK (under the Project No. 113T050) between Flanders and Turkey. 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. D.C. is supported by a FWO Pegasus-short Marie Curie Fellowship. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship. E.D. acknowledges support from Bilim Akademisi – The Science Academy, Turkey under the BAGEP program. ; Approved Most recent IF: 4.123; 2015 IF: 4.493
  Call Number c:irua:126394 Serial 2835
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Author Ao, Z.M.; Hernández-Nieves, A.D.; Peeters, F.M.; Li, S.
  Title The electric field as a novel switch for uptake/release of hydrogen for storage in nitrogen doped graphene Type A1 Journal article
  Year 2012 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 14 Issue 4 Pages 1463-1467
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Nitrogen-doped graphene was recently synthesized and was reported to be a catalyst for hydrogen dissociative adsorption under a perpendicular applied electric field (F). In this work, the diffusion of H atoms on N-doped graphene, in the presence and absence of an applied perpendicular electric field, is studied using density functional theory. We demonstrate that the applied field can significantly facilitate the binding of hydrogen molecules on N-doped graphene through dissociative adsorption and diffusion on the surface. By removing the applied field the absorbed H atoms can be released efficiently. Our theoretical calculation indicates that N-doped graphene is a promising hydrogen storage material with reversible hydrogen adsorption/desorption where the applied electric field can act as a switch for the uptake/release processes.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000298754500018 Publication Date 2011-11-21
  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 67 Open Access
  Notes ; Financial support of the Vice-Chancellor's Postdoctoral Research Fellowship Program (SIR50/PS19184) and the ECR grant (SIR30/PS24201) from the University of New South Wales are acknowledged. This work is also supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 4.123; 2012 IF: 3.829
  Call Number UA @ lucian @ c:irua:96266 Serial 3578
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Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
  Title The role of the VZn-NO-H complex in the p-type conductivity in ZnO Type A1 Journal article
  Year 2015 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 17 Issue 17 Pages 5485-5489
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000349616400080 Publication Date 2015-01-20
  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 20 Open Access
  Notes FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules Approved Most recent IF: 4.123; 2015 IF: 4.493
  Call Number c:irua:123218 Serial 3592
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Author Zeng, Y.I.; Menghini, M.; Li, D.Y.; Lin, S.S.; Ye, Z.Z.; Hadermann, J.; Moorkens, T.; Seo, J.W.; Locquet, J.-P.; van Haesendonck, C.
  Title Unexpected optical response of single ZnO nanowires probed using controllable electrical contacts Type A1 Journal article
  Year 2011 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 13 Issue 15 Pages 6931-6935
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Relying on combined electron-beam lithography and lift-off methods Au/Ti bilayer electrical contacts were attached to individual ZnO nanowires (NWs) that were grown by a vapor phase deposition method. Reliable Schottky-type as well as ohmic contacts were obtained depending on whether or not an ion milling process was used. The response of the ZnO NWs to ultraviolet light was found to be sensitive to the type of contacts. The intrinsic electronic properties of the ZnO NWs were studied in a field-effect transistor configuration. The transfer characteristics, including gate threshold voltage, hysteresis and operational mode, were demonstrated to unexpectedly respond to visible light. The origin of this effect could be accounted for by the presence of point defects in the ZnO NWs.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000288951000019 Publication Date 2011-03-14
  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 7 Open Access
  Notes Approved Most recent IF: 4.123; 2011 IF: 3.573
  Call Number UA @ lucian @ c:irua:89378 Serial 3807
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Author Filez, M.; Redekop, E.A.; Galvita, V.V.; Poelman, H.; Meledina, M.; Turner, S.; Van Tendeloo, G.; Bell, A.T.; Marin, G.B.
  Title The role of hydrogen during Pt-Ga nanocatalyst formation Type A1 Journal article
  Year 2016 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 18 Issue 18 Pages 3234-3243
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Hydrogen plays an essential role during the in situ assembly of tailored catalytic materials, and serves as key ingredient in multifarious chemical reactions promoted by these catalysts. Despite intensive debate for several decades, the existence and nature of hydrogen-involved mechanisms – such as hydrogen-spillover, surface migration – have not been unambiguously proven and elucidated up to date. Here, Pt-Ga alloy formation is used as a probe reaction to study the behavior and atomic transport of H and Ga, starting from Pt nanoparticles on hydrotalcite-derived Mg(Ga)(Al)Ox supports. In situ XANES spectroscopy, time-resolved TAP kinetic experiments, HAADF-STEM imaging and EDX mapping are combined to probe Pt, Ga and H in a series of H2 reduction experiments up to 650 degrees C. Mg(Ga)(Al)Ox by itself dissociates hydrogen, but these dissociated hydrogen species do not induce significant reduction of Ga3+ cations in the support. Only in the presence of Pt, partial reduction of Ga3+ into Gadelta+ is observed, suggesting that different reaction mechanisms dominate for Pt- and Mg(Ga)(Al)Ox-dissociated hydrogen species. This partial reduction of Ga3+ is made possible by Pt-dissociated H species which spillover onto non-reducible Mg(Al)Ox or partially reducible Mg(Ga)(Al)Ox and undergo long-range transport over the support surface. Moderately mobile Gadelta+Ox migrates towards Pt clusters, where Gadelta+ is only fully reduced to Ga0 on condition of immediate stabilization inside Pt-Ga alloyed nanoparticles.
  Address Laboratory for Chemical Technology (LCT), Ghent University, Technologiepark 914, B-9052 Ghent, Belgium. hilde.poelman@ugent.be
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language English Wos 000369506000106 Publication Date 2016-01-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 10 Open Access
  Notes This work was supported by the Fund for Scientific Research Flanders (FWO: G.0209.11), the ‘Long Term Structural Methusalem Funding by the Flemish Government’, the IAP 7/05 Interuniversity Attraction Poles Programme – Belgian State – Belgian Science Policy, and the Fund for Scientific Research Flanders (FWO-Vlaanderen) in supplying financing of beam time at the DUBBLE beam line of the ESRF and travel costs and a postdoctoral fellowship for S.T. The authors acknowledge the assistance from D. Banerjee (XAS campaign 26-01-979) at DUBBLE. E. A. Redekop acknowledges the Marie Curie International Incoming Fellowship granted by the European Commission (Grant Agreement No. 301703). The authors also express their gratitude to V. Bliznuk for acquisition of the TEM images. Approved Most recent IF: 4.123
  Call Number c:irua:132315 Serial 4000
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Author Bercx, M.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.
  Title First-principles analysis of the spectroscopic limited maximum efficiency of photovoltaic absorber layers for CuAu-like chalcogenides and silicon Type A1 Journal article
  Year 2016 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 18 Issue 18 Pages 20542-20549
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract Chalcopyrite semiconductors are of considerable interest for application as absorber layers in thin-film photovoltaic cells. When growing films of these compounds, however, they are often found to contain CuAu-like domains, a metastable phase of chalcopyrite. It has been reported that for CuInS2, the presence of the CuAu-like phase improves the short circuit current of the chalcopyrite-based photovoltaic cell. We investigate the thermodynamic stability of both phases for a selected list of I-III-VI2 materials using a first-principles density functional theory approach. For the CuIn-VI2 compounds, the difference in formation energy between the chalcopyrite and CuAu-like phase is found to be close to 2 meV per atom, indicating a high likelihood of the presence of CuAu-like domains. Next, we calculate the spectroscopic limited maximum efficiency (SLME) of the CuAu-like phase and compare the results with those of the corresponding chalcopyrite phase. We identify several candidates with a high efficiency, such as CuAu-like CuInS2, for which we obtain an SLME of 29% at a thickness of 500 nm. We observe that the SLME can have values above the Shockley-Queisser (SQ) limit, and show that this can occur because the SQ limit assumes the absorptivity to be a step function, thus overestimating the radiative recombination in the detailed balance approach. This means that it is possible to find higher theoretical efficiencies within this framework simply by calculating the J-V characteristic with an absorption spectrum. Finally, we expand our SLME analysis to indirect band gap absorbers by studying silicon, and find that the SLME quickly overestimates the reverse saturation current of indirect band gap materials, drastically lowering their calculated efficiency.
  Address EMAT & CMT groups, Department of Physics, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171, 2020 Antwerp, Belgium. marnik.bercx@uantwerpen.be
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language English Wos 000381428600058 Publication Date 2016-07-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 34 Open Access
  Notes We acknowledge financial support of FWO-Vlaanderen through projects G.0150.13N and G.0216.14N and ERA-NET RUS Plus/FWO, Grant G0D6515N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO FWOVlaanderen. Approved Most recent IF: 4.123
  Call Number c:irua:135091 Serial 4112
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Author Aierken, Y.; Leenaerts, O.; Peeters, F.M.
  Title A first-principles study of stable few-layer penta-silicene Type A1 Journal article
  Year 2016 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 18 Issue 18 Pages 18486-18492
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Recently penta-graphene was proposed as a stable two-dimensional carbon allotrope consisting of a single layer of interconnected carbon pentagons [Zhang et al., PNAS, 2015, 112, 2372]. Its silicon counterpart, penta-silicene, however, is not stable. In this work, we show that multilayers of penta-silicene form stable materials with semiconducting or metallic properties, depending on the stacking mode. We demonstrate their dynamic stability through their phonon spectrum and using molecular dynamics. A particular type of bilayer penta-silicene is found to have lower energy than all of the known hexagonal silicene bilayers and forms therefore the most stable bilayer silicon material predicted so far. The electronic and mechanical properties of these new silicon allotropes are studied in detail and their behavior under strain is investigated. We demonstrate that strain can be used to tune its band gap.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000379486200077 Publication Date 2016-06-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 42 Open Access
  Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources 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: 4.123
  Call Number UA @ lucian @ c:irua:134942 Serial 4132
Permanent link to this record
 

 
Author Çakir, D.; Peeters, F.M.
  Title Fluorographane : a promising material for bipolar doping of MoS2 Type A1 Journal article
  Year 2015 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 17 Issue 17 Pages 27636-27641
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using first principles calculations we investigate the structural and electronic properties of interfaces between fluorographane and MoS2. Unsymmetrical functionalization of graphene with H and F results in an intrinsic dipole moment perpendicular to the plane of the buckled graphene skeleton. Depending on the orientation of this dipole moment, the electronic properties of a physically absorbed MoS2 monolayer can be switched from n-to p-type or vice versa. We show that one can realize vanishing n-type/p-type Schottky barrier heights when contacting MoS2 to fluorographane. By applying a perpendicular electric field, the size of the Schottky barrier and the degree of doping can be tuned. Our calculations indicate that a fluorographane monolayer is a promising candidate for bipolar doping of MoS2, which is vital in the design of novel technological applications based on two-dimensional materials.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000363193800043 Publication Date 2015-09-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 7 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid 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: 4.123; 2015 IF: 4.493
  Call Number UA @ lucian @ c:irua:129477 Serial 4182
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Author Calizzi, M.; Venturi, F.; Ponthieu, M.; Cuevas, F.; Morandi, V.; Perkisas, T.; Bals, S.; Pasquini, L.
  Title Gas-phase synthesis of Mg-Ti nanoparticles for solid-state hydrogen storage Type A1 Journal article
  Year 2016 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 18 Issue 18 Pages 141-148
  Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT)
  Abstract Mg-Ti nanostructured samples with different Ti contents were prepared via compaction of nanoparticles grown by inert gas condensation with independent Mg and Ti vapour sources. The growth set-up offered the option to perform in situ hydrogen absorption before compaction. Structural and morphological characterisation was carried out by X-ray diffraction, energy dispersive spectroscopy and electron microscopy. The formation of an extended metastable solid solution of Ti in hcp Mg was detected up to 15 at% Ti in the as-grown nanoparticles, while after in situ hydrogen absorption, phase separation between MgH2 and TiH2 was observed. At a Ti content of 22 at%, a metastable Mg-Ti-H fcc phase was observed after in situ hydrogen absorption. The co-evaporation of Mg and Ti inhibited nanoparticle coalescence and crystallite growth in comparison with the evaporation of Mg only. In situ hydrogen absorption was beneficial to subsequent hydrogen behaviour, studied by high pressure differential scanning calorimetry and isothermal kinetics. A transformed fraction of 90% was reached within 100 s at 300 degrees C during both hydrogen absorption and desorption. The enthalpy of hydride formation was not observed to differ from bulk MgH2.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000368755500014 Publication Date 2015-11-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 31 Open Access Not_Open_Access
  Notes ; Part of this work was supported by the COST Action MP1103 “Nanostructured materials for solid-state hydrogen storage”. ; Approved Most recent IF: 4.123
  Call Number UA @ lucian @ c:irua:131589 Serial 4184
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Author Kang, J.; Sahin, H.; Peeters, F.M.
  Title Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 Type A1 Journal article
  Year 2015 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 17 Issue 17 Pages 27742-27749
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000363193800055 Publication Date 2015-09-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 83 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. 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 Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; Approved Most recent IF: 4.123; 2015 IF: 4.493
  Call Number UA @ lucian @ c:irua:129478 Serial 4204
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Author Yagmurcukardes, M.; Horzum, S.; Torun, E.; Peeters, F.M.; Senger, R.T.
  Title Nitrogenated, phosphorated and arsenicated monolayer holey graphenes Type A1 Journal article
  Year 2016 Publication (down) Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 18 Issue 18 Pages 3144-3150
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Motivated by a recent experiment that reported the synthesis of a new 2D material nitrogenated holey graphene (C2N) [Mahmood et al., Nat. Commun., 2015, 6, 6486], the electronic, magnetic, and mechanical properties of nitrogenated (C2N), phosphorated (C2P) and arsenicated (C2As) monolayer holey graphene structures are investigated using first-principles calculations. Our total energy calculations indicate that, similar to the C2N monolayer, the formation of the other two holey structures are also energetically feasible. Calculated cohesive energies for each monolayer show a decreasing trend going from the C2N to C2As structure. Remarkably, all the holey monolayers considered are direct band gap semiconductors. Regarding the mechanical properties (in-plane stiffness and Poisson ratio), we find that C2N has the highest in-plane stiffness and the largest Poisson ratio among the three monolayers. In addition, our calculations reveal that for the C2N, C2P and C2As monolayers, creation of N and P defects changes the semiconducting behavior to a metallic ground state while the inclusion of double H impurities in all holey structures results in magnetic ground states. As an alternative to the experimentally synthesized C2N, C2P and C2As are mechanically stable and flexible semiconductors which are important for potential applications in optoelectronics.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000369506000095 Publication Date 2015-12-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 36 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; Approved Most recent IF: 4.123
  Call Number UA @ lucian @ c:irua:132313 Serial 4214
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