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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 | 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. | ||||
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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 | 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 | 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. | ||||
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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 | 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. | ||||
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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 | 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 | 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. | ||||
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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 | 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. | ||||
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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 | 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 | |||||
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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 | 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. | ||||
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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 | Shanenko, A.A. | ||||
Title | Imperfect fermi gas : kinetic and interaction energies | Type | A1 Journal article | ||
Year | 2004 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
Volume | 70 | Issue | 6 | Pages | 063618-13 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | A uniform ground-state three-dimensional Fermi gas with short-range repulsive pairwise interaction is under consideration. Its kinetic and interaction energies are calculated up to the second order of the expansion in the gas parameter. Similar to recent results for an interacting Bose gas, the quantities in question are found to depend on the pairwise interaction through two characteristic lengths: the former, a, is the s-wave scattering length, and the latter, b, is related to a by b=a-m(partial derivativea/partial derivativem), where m stands for the fermion mass. To control the results, we proceed in two independent ways. The first involves the Hellmann-Feynman theorem applied to derive the kinetic and interaction energies from the total-energy expansion in the gas parameter first found by Huang and Yang. The second way operates with in-medium pair wave functions and allows one to calculate the quantities of interest “from scratch.” The results of the present investigation, taken together with those of the recent consideration of a dilute Bose gas, make it possible to conclude that the pairwise interaction in a quantum gas has an essential and nontrivial effect on the kinetic energy, which is not the case for a classical many-particle system. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000226418900116 | Publication Date | 2004-12-22 | |
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 | |
Impact Factor | 2.925 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 2.925; 2004 IF: 2.902 | |||
Call Number | UA @ lucian @ c:irua:103196 | Serial | 1562 | ||
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Author | Van Boxem, R.; Partoens, B.; Verbeeck, J. | ||||
Title | Inelastic electron-vortex-beam scattering | Type | A1 Journal article | ||
Year | 2015 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
Volume | 91 | Issue | 91 | Pages | 032703 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | Recent theoretical and experimental developments in the field of electron-vortex-beam physics have raised questions about what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part of the answer to these questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and postselection one can filter out the relevant contributions to a specific signal. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000351035000004 | Publication Date | 2015-03-16 | |
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 | 31 | Open Access | |
Notes | Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.925; 2015 IF: 2.808 | ||
Call Number | c:irua:123925 c:irua:123925UA @ admin @ c:irua:123925 | Serial | 1607 | ||
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Author | Van Boxem, R.; Partoens, B.; Verbeeck, J. | ||||
Title | Rutherford scattering of electron vortices | Type | A1 Journal article | ||
Year | 2014 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
Volume | 89 | Issue | 3 | Pages | 032715-32719 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | By considering a cylindrically symmetric generalization of a plane wave, the first-order Born approximation of screened Coulomb scattering unfolds two new dimensions in the scattering problem: transverse momentum and orbital angular momentum of the incoming beam. In this paper, the elastic Coulomb scattering amplitude is calculated analytically for incoming Bessel beams. This reveals novel features occurring for wide-angle scattering and quantitative insights for small-angle vortex scattering. The result successfully generalizes the well-known Rutherford formula, incorporating transverse and orbital angular momentum into the formalism. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000333690500008 | Publication Date | 2014-03-31 | |
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 | 312483-Esteem2; N246791 – Countatoms; 278510 Vortex; esteem2jra1; esteem2jra3 ECASJO_; | Approved | Most recent IF: 2.925; 2014 IF: 2.808 | ||
Call Number | UA @ lucian @ c:irua:115562UA @ admin @ c:irua:115562 | Serial | 2936 | ||
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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 | 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. | ||||
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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 | 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. | ||||
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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 | 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. | ||||
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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 | 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 | 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. | ||||
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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 | ||
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Author | Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.; Volety, K.; Huyberechts, G.; Paul, J. | ||||
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. | ||||
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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 | ; 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 | ||
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Author | Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
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. | ||||
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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 | ; 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 | ||
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Author | Verberck, B.; Okazaki, T.; Tarakina, N.V. | ||||
Title | Ordered and disordered packing of coronene molecules in carbon nanotubes | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 15 | Issue | 41 | Pages | 18108-18114 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Monte Carlo simulations of coronene molecules in single-walled carbon nanotubes (SWCNTs) and dicoronylene molecules in SWCNTs are performed. Depending on the diameter D of the encapsulating SWCNT, regimes favoring the formation of ordered, one-dimensional (1D) stacks of tilted molecules (D <= 1.7 nm for coronene@SWCNT, 1.5 nm <= D <= 1.7 nm for dicoronylene@SWCNT) and regimes with disordered molecular arrangements and increased translational mobilities enabling the thermally induced polymerization of neighboring molecules resulting in the formation of graphene nanoribbons (GNRs) are observed. The results show that the diameter of the encapsulating nanotube is a crucial parameter for the controlled synthesis of either highly ordered 1D structures or GNR precursors. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000325400600045 | Publication Date | 2013-09-05 | |
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 | 9 | Open Access | |
Notes | ; B.V. is a Postdoctoral Fellow of the Research Foundation Flanders (FWO-VI). N.V.T. acknowledges funding by the Bavarian Ministry of Sciences, Research and the Arts. ; | Approved | Most recent IF: 4.123; 2013 IF: 4.198 | ||
Call Number | UA @ lucian @ c:irua:112212 | Serial | 2502 | ||
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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 | 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 | Brito, B.G.A.; Hai, G.-Q.; Teixeira Rabelo, J.N.; Cândido, L. | ||||
Title | A quantum Monte Carlo study on electron correlation in all-metal aromatic clusters MAl4 – (M = Li, Na, K, Rb, Cu, Ag and Au) | Type | A1 Journal article | ||
Year | 2014 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 16 | Issue | 18 | Pages | 8639-8645 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using fixed-node diffusion quantum Monte Carlo (FN-DMC) simulation we investigate the electron correlation in all-metal aromatic clusters MAl4- (with M = Li, Na, K, Rb, Cu, Ag and Au). The electron detachment energies and electron affinities of the clusters are obtained. The vertical electron detachment energies obtained from the FN-DMC calculations are in very good agreement with the available experimental results. Calculations are also performed within the Hartree-Fock approximation, density-functional theory (DFT), and the couple-cluster (CCSD(T)) method. From the obtained results, we analyse the impact of the electron correlation effects in these bimetallic clusters and find that the correlation of the valence electrons contributes significantly to the detachment energies and electron affinities, varying between 20% and 50% of their total values. Furthermore, we discuss the electron correlation effects on the stability of the clusters as well as the accuracy of the DFT and CCSD(T) calculations in the present systems. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000334602900052 | Publication Date | 2014-03-21 | |
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 | 10 | Open Access | |
Notes | ; This research was supported by CNPq, FAPESP and FAPEG (Brazil). ; | Approved | Most recent IF: 4.123; 2014 IF: 4.493 | ||
Call Number | UA @ lucian @ c:irua:117247 | Serial | 2781 | ||
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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 | 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. | ||||
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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 | Schoeters, B.; Neyts, E.C.; Khalilov, U.; Pourtois, G.; Partoens, B. | ||||
Title | Stability of Si epoxide defects in Si nanowires : a mixed reactive force field/DFT study | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 15 | Issue | 36 | Pages | 15091-15097 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Modeling the oxidation process of silicon nanowires through reactive force field based molecular dynamics simulations suggests that the formation of Si epoxide defects occurs both at the Si/SiOx interface and at the nanowire surface, whereas for flat surfaces, this defect is experimentally observed to occur only at the interface as a result of stress. In this paper, we argue that the increasing curvature stabilizes the defect at the nanowire surface, as suggested by our density functional theory calculations. The latter can have important consequences for the opto-electronic properties of thin silicon nanowires, since the epoxide induces an electronic state within the band gap. Removing the epoxide defect by hydrogenation is expected to be possible but becomes increasingly difficult with a reduction of the diameter of the nanowires. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000323520600029 | Publication Date | 2013-07-16 | |
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 | 3 | Open Access | |
Notes | ; BS gratefully acknowledges financial support of the IWT, Institute for the Promotion of Innovation by Science and Technology in Flanders, via the SBO project “SilaSol”. This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. ; | Approved | Most recent IF: 4.123; 2013 IF: 4.198 | ||
Call Number | UA @ lucian @ c:irua:110793 | Serial | 3130 | ||
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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 | 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. | ||||
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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 | 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. | ||||
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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 | 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 | 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 | 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. | ||||
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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 | ||
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Author | Çakir, D.; Peeters, F.M. | ||||
Title | Fluorographane : a promising material for bipolar doping of MoS2 | Type | A1 Journal article | ||
Year | 2015 | Publication | 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. | ||||
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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 | 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 | 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. | ||||
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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 | 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. | ||||
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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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Author | Matsubara, M.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
Title | Doping anatase TiO2with group V-b and VI-b transition metal atoms: a hybrid functional first-principles study | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 19 | Issue | 19 | Pages | 1945-1952 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the role of transition metal atoms of group V-b (V, Nb, Ta) and VI-b (Cr, Mo, W) as n- or p-type dopants in anatase TiO$2$ using thermodynamic principles and density functional theory with the Heyd-Scuseria-Ernzerhof HSE06 hybrid functional. The HSE06 functional provides a realistic value for the band gap, which ensures a correct classification of dopants as shallow or deep donors or acceptors. Defect formation energies and thermodynamic transition levels are calculated taking into account the constraints imposed by the stability of TiO$2$ and the solubility limit of the impurities. Nb, Ta, W and Mo are identified as shallow donors. Although W provides two electrons, Nb and Ta show a considerable lower formation energy, in particular under O-poor conditions. Mo donates in principle one electron, but under specific conditions can turn into a double donor. V impurities are deep donors and Cr shows up as an amphoteric defect, thereby acting as an electron trapping center in n-type TiO$_2$ especially under O-rich conditions. A comparison with the available experimental data yields excellent agreement. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000394426400027 | Publication Date | 2016-12-12 | |
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 | 19 | Open Access | OpenAccess |
Notes | We gratefully acknowledge financial support from the IWTVlaanderenthrough projects G.0191.08 and G.0150.13, and the BOF-NOI of 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. M. M. acknowledges financial support from the GOA project ‘‘XANES meets ELNES’’ of the University of Antwerp. | Approved | Most recent IF: 4.123 | ||
Call Number | EMAT @ emat @ c:irua:140835 | Serial | 4421 | ||
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Author | Aierken, Y.; Çakir, D.; Peeters, F.M. | ||||
Title | Strain enhancement of acoustic phonon limited mobility in monolayer TiS3 | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 18 | Issue | 18 | Pages | 14434-14441 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Strain engineering is an effective way to tune the intrinsic properties of a material. Here, we show by using first-principles calculations that both uniaxial and biaxial tensile strain applied to monolayer TiS3 are able to significantly modify its intrinsic mobility. From the elastic modulus and the phonon dispersion relation we determine the tensile strain range where structure dynamical stability of the monolayer is guaranteed. Within this region, we find more than one order of enhancement of the acoustic phonon limited mobility at 300 K (100 K), i.e. from 1.71 x 10(4) (5.13 x 10(4)) cm(2) V-1 s(-1) to 5.53 x 10(6) (1.66 x 10(6)) cm(2) V-1 s(-1). The degree of anisotropy in both mobility and effective mass can be tuned by using tensile strain. Furthermore, we can either increase or decrease the band gap of TiS3 monolayer by applying strain along different crystal directions. This property allows us to use TiS3 not only in electronic but also in optical applications. | ||||
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Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000378102700036 | Publication Date | 2016-05-05 | |
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 | 24 | Open Access | |
Notes | ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-V1). Computational resources were provided by 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-department EWI. ; | Approved | Most recent IF: 4.123 | ||
Call Number | UA @ lucian @ c:irua:134628 | Serial | 4250 | ||
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