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Author | Michel, K.H.; Costamagna; Peeters, F.M. | ||||
Title | Theory of thermal expansion in 2D crystals | Type | A1 Journal article | ||
Year | 2015 | Publication | Physica status solidi: B: basic research | Abbreviated Journal | Phys Status Solidi B |
Volume | 252 | Issue | 252 | Pages | 2433-2437 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Berlin | Editor | ||
Language | Wos | 000364690400014 | Publication Date | 2015-08-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0370-1972 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.674 | Times cited | 21 | Open Access | |
Notes | ; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; | Approved | Most recent IF: 1.674; 2015 IF: 1.489 | ||
Call Number | UA @ lucian @ c:irua:130281 | Serial | 4264 | ||
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Author | Van der Donck, M.; Peeters, F.M.; Van Duppen, B. | ||||
Title | Transport properties of bilayer graphene in a strong in-plane magnetic field | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 115423 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | A strong in-plane magnetic field drastically alters the low-energy spectrum of bilayer graphene by separating the parabolic energy dispersion into two linear Dirac cones. The effect of this dramatic change on the transport properties strongly depends on the orientation of the in-plane magnetic field with respect to the propagation direction of the charge carriers and the angle at which they impinge on the electrostatic potentials. For magnetic fields oriented parallel to the potential boundaries an additional propagating mode that results from the splitting into Dirac cones enhances the transmission probability for charge carriers tunneling through the potentials and increases the corresponding conductance. Our results show that the chiral suppression of transmission at normal incidence, reminiscent of bilayer graphene's 2 pi Berry phase, is turned into a chiral enhancement when the magnetic field increases, thus indicating a transition from a bilayer to a monolayer-like system at normal incidence. Further, we find that the typical transmission resonances stemming from confinement in a potential barrier are shifted to higher energy and are eventually transformed into antiresonances with increasing magnetic field. For magnetic fields oriented perpendicular to the potential boundaries we find a very pronounced transition from a bilayer system to two separated monolayer-like systems with Klein tunneling emerging at certain incident angles symmetric around 0, which also leaves a signature in the conductance. For both orientations of the magnetic field, the transmission probability is still correctly described by pseudospin conservation. Finally, to motivate the large in-plane magnetic field, we show that its energy spectrum can be mimicked by specific lattice deformations such as a relative shift of one of the layers. With this equivalence we introduce the notion of an in-plane pseudomagnetic field. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000372409900006 | Publication Date | 2016-03-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 11 | Open Access | |
Notes | ; This work was supported by Fonds Wetenschappelijk Onderzoek (FWO-Vl) through an aspirant research grant to M.V.D.D. and B.V.D. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:133197 | Serial | 4267 | ||
Permanent link to this record | |||||
Author | Grujić, M.M.; Ezawa, M.; Tadic, M.Z.; Peeters, F.M. | ||||
Title | Tunable skewed edges in puckered structures | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 245413 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We propose a type of edges arising due to the anisotropy inherent in the puckered structure of a honeycomb system such as in phosphorene. Skewed-zigzag and skewed-armchair nanoribbons are semiconducting and metallic, respectively, in contrast to their normal edge counterparts. Their band structures are tunable, and a metal-insulator transition is induced by an electric field. We predict a field-effect transistor based on the edge states in skewed-armchair nanoribbons, where the edge state is gapped by applying arbitrary small electric field E-z. A topological argument is presented, revealing the condition for the emergence of such edge states. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000377802700010 | Publication Date | 2016-06-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 29 | Open Access | |
Notes | ; This work was supported by the Serbian Ministry of Education, Science and Technological Development, and the Flemish Science Foundation (FWO-Vl). M.E. is thankful for the support by the Grants-in-Aid for Scientific Research from MEXT KAKENHI (Grants No. 25400317 and No. 15H05854). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:134599 | Serial | 4268 | ||
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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 | 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. | ||||
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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 | 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. | ||||
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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 | Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Collaert, N.; Mocuta, A.; Thean, A.; Groeseneken, G. | ||||
Title | Uniform strain in heterostructure tunnel field-effect transistors | Type | A1 Journal article | ||
Year | 2016 | Publication | IEEE electron device letters | Abbreviated Journal | Ieee Electr Device L |
Volume | 37 | Issue | 37 | Pages | 337-340 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Strain can strongly impact the performance of III-V tunnel field-effect transistors (TFETs). However, previous studies on homostructure TFETs have found an increase in ON-current to be accompanied with a degradation of subthreshold swing. We perform 30-band quantum mechanical simulations of staggered heterostructure p-n-i-n TFETs submitted to uniaxial and biaxial uniform stress and find the origin of the subthreshold degradation to be a reduction of the density of states in the strained case. We apply an alternative configuration including a lowly doped pocket in the source, which allows to take full benefit of the strain-induced increase in ON-current. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000372372100026 | Publication Date | 2016-01-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0741-3106 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.048 | Times cited | 17 | Open Access | |
Notes | ; This work was supported by the imec Industrial Affiliation Program. The work of D. Verreck was supported by the Agency for Innovation by Science and Technology in Flanders. The review of this letter was arranged by Editor Z. Chen. ; | Approved | Most recent IF: 3.048 | ||
Call Number | UA @ lucian @ c:irua:133207 | Serial | 4271 | ||
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Author | Moors, K.; Sorée, B.; Magnus, W. | ||||
Title | Validity criteria for Fermi's golden rule scattering rates applied to metallic nanowires | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of physics : condensed matter | Abbreviated Journal | J Phys-Condens Mat |
Volume | 28 | Issue | 28 | Pages | 365302 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Fermi's golden rule underpins the investigation of mobile carriers propagating through various solids, being a standard tool to calculate their scattering rates. As such, it provides a perturbative estimate under the implicit assumption that the effect of the interaction Hamiltonian which causes the scattering events is sufficiently small. To check the validity of this assumption, we present a general framework to derive simple validity criteria in order to assess whether the scattering rates can be trusted for the system under consideration, given its statistical properties such as average size, electron density, impurity density et cetera. We derive concrete validity criteria for metallic nanowires with conduction electrons populating a single parabolic band subjected to different elastic scattering mechanisms: impurities, grain boundaries and surface roughness. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | London | Editor | ||
Language | Wos | 000380754400013 | Publication Date | 2016-07-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0953-8984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.649 | Times cited | 2 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.649 | ||
Call Number | UA @ lucian @ c:irua:135011 | Serial | 4274 | ||
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Author | Fernández Becerra, V.; Sardella, E.; Peeters, F.M.; Milošević, M.V. | ||||
Title | Vortical versus skyrmionic states in mesoscopic p-wave superconductors | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 014518 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the superconducting states that arise as a consequence of mesoscopic confinement and a multicomponent order parameter in the Ginzburg-Landau model for p-wave superconductivity. Conventional vortices, but also half-quantum vortices and skyrmions, are found as the applied magnetic field and the anisotropy parameters of the Fermi surface are varied. The solutions are well differentiated by a topological charge that for skyrmions is given by the Hopf invariant and for vortices by the circulation of the superconducting velocity. We revealed several unique states combining vortices and skyrmions, their possible reconfiguration with varied magnetic field, as well as temporal and field-induced transitions between vortical and skyrmionic states. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000369217400004 | Publication Date | 2016-01-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 28 | Open Access | |
Notes | ; This work was supported by the Research Foundation – Flanders (FWO). E.S. acknowledges support from the Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:131581 | Serial | 4275 | ||
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Author | Matulis, A.; Zarenia, M.; Peeters, F.M. | ||||
Title | Wave fronts and packets in 1D models of different meta-materials : graphene, left-handed media and transmission line | Type | A1 Journal article | ||
Year | 2015 | Publication | Physica status solidi: B: basic research | Abbreviated Journal | Phys Status Solidi B |
Volume | 252 | Issue | 252 | Pages | 2330-2338 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | A comparative study is made of the propagation of wave packets and fronts in three different meta-media, i.e. graphene, left-handed media (LHM) and transmission lines, using one-dimensional models. It is shown that a potential step in graphene influences only the frequency of the electronic wave, i.e., the particular spectrum branch (electron or hole) to which the wave belongs to, while the envelop function (the wave front or packet form) remains unchanged. Although the model for a vacuum and LHM interface is similar to that of the potential step in graphene, the solutions are quite different due to differences in the chirality of the waves. Comparing the propagation of wave fronts and packets in a standard transmission line and its meta-analog we demonstrate that the propagating packets in the meta-line are much more deformed as compared to the standard one, including broadening, asymmetry and even the appearance of fast moving precursors. This influence is seen not only in the case of packets with steep fronts but in soft Gaussian packets as well. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Berlin | Editor | ||
Language | Wos | 000362722300025 | Publication Date | 2015-07-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0370-1972 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.674 | Times cited | 1 | Open Access | |
Notes | ; This work was financially supported by the Flemish Science Foundation (FWO-Vl), the Methusalem foundation of the Flemish government, and the European Social Fund under the Global Grant Measure (Grant No. VP1-3.1-SMM-07-K-02-046). ; | Approved | Most recent IF: 1.674; 2015 IF: 1.489 | ||
Call Number | UA @ lucian @ c:irua:128776 | Serial | 4277 | ||
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Author | Callewaert, V.; Saniz, R.; Barbiellini, B.; Partoens, B. | ||||
Title | Surface states and positron annihilation spectroscopy: results and prospects from a first-principles approach | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of physics : conference series | Abbreviated Journal | |
Volume | 791 | Issue | 791 | Pages | 012036 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The trapping of positrons at the surface of a material can be exploited to study quite selectively the surface properties of the latter by means of positron annihilation spectroscopy techniques. To support these, it is desirable to be able to theoretically predict the existence of such positronic surface states and to describe their annihilation characteristics with core or valence surface electrons in a reliable way. Here, we build on the well-developed first-principles techniques for the study of positrons in bulk solids as well as on previous models for surfaces, and investigate two schemes that can improve the theoretical description of the interaction of positrons with surfaces. One is based on supplementing the local-density correlation potential with the corrugated image potential at the surface, and the other is based on the weighted-density approximation to correlation. We discuss our results for topological insulators, graphene layers, and quantum dots, with emphasis on the information that can be directly related to experiment. We also discuss some open theoretical problems that should be addressed by future research. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000400610500036 | Publication Date | 2017-02-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1742-6588 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 1 | Open Access | ||
Notes | We acknowledge financial support from FWO-Vlaanderen (projects G.0150.13 and G.0224.14N). This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), funded by the Hercules foundation and the Flemish Government (EWI Department). The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University’s Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02- 05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. | Approved | Most recent IF: NA | ||
Call Number | CMT @ cmt @ c:irua:140847 | Serial | 4425 | ||
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Author | Zhang, L.; Fernández Becerra, V.; Covaci, L.; Milošević, M.V. | ||||
Title | Electronic properties of emergent topological defects in chiral p-wave superconductivity | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 024520 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Chiral p-wave superconductors in applied magnetic field can exhibit more complex topological defects than just conventional superconducting vortices, due to the two-component order parameter (OP) and the broken time-reversal symmetry. We investigate the electronic properties of those exotic states, some of which contain clusters of one-component vortices in chiral components of the OP and/or exhibit skyrmionic character in the relative OP space, all obtained as a self-consistent solution of the microscopic Bogoliubov-de Gennes equations. We reveal the link between the local density of states (LDOS) of the novel topological states and the behavior of the chiral domain wall between the OP components, enabling direct identification of those states in scanning tunneling microscopy. For example, a skyrmion always contains a closed chiral domain wall, which is found to be mapped exactly by zero-bias peaks in LDOS. Moreover, the LDOS exhibits electron-hole asymmetry, which is different from the LDOS of conventional vortex states with same vorticity. Finally, we present the magnetic field and temperature dependence of the properties of a skyrmion, indicating that this topological defect can be surprisingly large in size, and can be pinned by an artificially indented nonsuperconducting closed path in the sample. These features are expected to facilitate the experimental observation of skyrmionic states, thereby enabling experimental verification of chirality in emerging superconducting materials. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000381479500002 | Publication Date | 2016-07-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 27 | Open Access | |
Notes | ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:135742 | Serial | 4303 | ||
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Author | Sisakht, E.T.; Fazileh, F.; Zare, M.H.; Zarenia, M.; Peeters, F.M. | ||||
Title | Strain-induced topological phase transition in phosphorene and in phosphorene nanoribbons | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 085417 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the tight-binding (TB) approximation with inclusion of the spin-orbit interaction, we predict a topological phase transition in the electronic band structure of phosphorene in the presence of axial strains. We derive a low-energy TB Hamiltonian that includes the spin-orbit interaction for bulk phosphorene. Applying a compressive biaxial in-plane strain and perpendicular tensile strain in ranges where the structure is still stable leads to a topological phase transition. We also examine the influence of strain on zigzag phosphorene nanoribbons (zPNRs) and the formation of the corresponding protected edge states when the system is in the topological phase. For zPNRs up to a width of 100 nm the energy gap is at least three orders of magnitude larger than the thermal energy at room temperature. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000381600800004 | Publication Date | 2016-08-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 76 | Open Access | |
Notes | ; This work was supported by Ministry of Science, Research and Technology, Iran. M.Z. acknowledges support as a postdoctoral fellow of the Flemish Research Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:135643 | Serial | 4309 | ||
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Author | Bekaert, J.; Vercauteren, S.; Aperis, A.; Komendová, L.; Prozorov, R.; Partoens, B.; Milošević, M.V. | ||||
Title | Anisotropic type-I superconductivity and anomalous superfluid density in OsB2 | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 144506 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a microscopic study of superconductivity in OsB2 , and discuss the origin and characteristic length scales of the superconducting state. From first-principles we show that OsB2 is characterized by three different Fermi sheets, and we prove that this fermiology complies with recent quantum-oscillation experiments. Using the found microscopic properties, and experimental data from the literature, we employ Ginzburg-Landau relations to reveal that OsB2 is a distinctly type-I superconductor with a very low Ginzburg-Landau parameter κ—a rare property among compound materials. We show that the found coherence length and penetration depth corroborate the measured thermodynamic critical field. Moreover, our calculation of the superconducting gap structure using anisotropic Eliashberg theory and ab initio calculated electron-phonon interaction as input reveals a single but anisotropic gap. The calculated gap spectrum is shown to give an excellent account for the unconventional behavior of the superfluid density of OsB2 measured in experiments as a function of temperature. This reveals that gap anisotropy can explain such behavior, observed in several compounds, which was previously attributed solely to a two-gap nature of superconductivity. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000385622500009 | Publication Date | 2016-10-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 19 | Open Access | |
Notes | Fonds Wetenschappelijk Onderzoek; European Cooperation in Science and Technology, MP1201 ; Vetenskapsrådet; | Approved | Most recent IF: 3.836 | ||
Call Number | CMT @ cmt @ c:irua:139020 | Serial | 4338 | ||
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Author | Ackerman, M.L.; Kumar, P.; Neek-Amal, M.; Thibado, P.M.; Peeters, F.M.; Singh, S. | ||||
Title | Anomalous dynamical behavior of freestanding graphene membranes | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 117 | Issue | 117 | Pages | 126801 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We report subnanometer, high-bandwidth measurements of the out-of-plane (vertical) motion of atoms in freestanding graphene using scanning tunneling microscopy. By tracking the vertical position over a long time period, a 1000-fold increase in the ability to measure space-time dynamics of atomically thin membranes is achieved over the current state-of-the-art imaging technologies. We observe that the vertical motion of a graphene membrane exhibits rare long-scale excursions characterized by both anomalous mean-squared displacements and Cauchy-Lorentz power law jump distributions. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000383171800010 | Publication Date | 2016-09-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 46 | Open Access | |
Notes | ; The authors thank Theodore L. Einstein, Michael F. Shlesinger, and Woodrow L. Shew for their careful reading of the manuscript and insightful comments. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. P. M. T. was supported by the Office of Naval Research under Grant No. N00014-10-1-0181 and the National Science Foundation under Grant No. DMR-0855358. M.N.-A. was supported by Iran Science Elites Federation (ISEF) under Grant No. 11/66332. ; | Approved | Most recent IF: 8.462 | ||
Call Number | UA @ lucian @ c:irua:137125 | Serial | 4347 | ||
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Author | De Beule, C.; Ziani, N.T.; Zarenia, M.; Partoens, B.; Trauzettel, B. | ||||
Title | Correlation and current anomalies in helical quantum dots | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 155111 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We theoretically investigate the ground-state properties of a quantum dot defined on the surface of a strong three-dimensional time-reversal invariant topological insulator. Confinement is realized by ferromagnetic barriers and Coulomb interaction is treated numerically for up to seven electrons in the dot. Experimentally relevant intermediate interaction strengths are considered. The topological origin of the dot has several consequences: (i) spin polarization increases and the ground state exhibits quantum phase transitions at specific angular momenta as a function of interaction strength, (ii) the onset of Wigner correlations takes place mainly in one spin channel, and (iii) the ground state is characterized by a robust persistent current that changes sign as a function of the distance from the center of the dot. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000385242200001 | Publication Date | 2016-10-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 3 | Open Access | |
Notes | ; We thank F. Cavaliere, F. Crepin, C. Felser, and B. Yan for interesting discussions, and S. Curreli for performing the finite-element calculation of the magnetic field in COMSOL. C.D.B. and M.Z. are supported by the Flemish Research Foundation (FWO). N.T.Z. and B.T. acknowledge financial support by the DFG (SPP1666 and SFB1170 “ToCoTronics”), the Helmholtz Foundation (VITI), and the ENB Graduate School on “Topological Insulators.” ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:137234 | Serial | 4351 | ||
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Author | Mirzakhani, M.; Zarenia, M.; da Costa, D.R.; Ketabi, S.A.; Peeters, F.M. | ||||
Title | Energy levels of ABC-stacked trilayer graphene quantum dots with infinite-mass boundary conditions | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 165423 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the continuum model, we investigate the confined states and the corresponding wave functions of ABC-stacked trilayer graphene (TLG) quantum dots (QDs). First, a general infinite-mass boundary condition is derived and applied to calculate the electron and hole energy levels of a circular QD in both the absence and presence of a perpendicular magnetic field. Our analytical results for the energy spectra agree with those obtained by using the tight-binding model, where a TLG QD is surrounded by a staggered potential. Our findings show that (i) the energy spectrum exhibits intervalley symmetry E-K(e)(m) = -E-K'(h)(m) for the electron (e) and hole (h) states, where m is the angular momentum quantum number, (ii) the zero-energy Landau level (LL) is formed by the magnetic states with m <= 0 for both Dirac valleys, that is different from monolayer and bilayer graphene QD with infinite-mass potential in which only one of the cones contributes, and (iii) groups of three quantum Hall edge states in the tight-binding magnetic spectrum approach the zero LL, which results from the layer symmetry in TLG QDs. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000386168000011 | Publication Date | 2016-10-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 9 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Brazilian Council for Research (CNPq), the Science without Borders program, PRONEX/FUNCAP, and CAPES foundation. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:138174 | Serial | 4353 | ||
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Author | Stosic, D.; Stosic, D.; Ludermir, T.; Stosic, B.; Milošević, M.V. | ||||
Title | GPU-advanced 3D electromagnetic simulations of superconductors in the Ginzburg-Landau formalism | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of computational physics | Abbreviated Journal | J Comput Phys |
Volume | 322 | Issue | 322 | Pages | 183-198 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Ginzburg-Landau theory is one of the most powerful phenomenological theories in physics, with particular predictive value in superconductivity. The formalism solves coupled nonlinear differential equations for both the electronic and magnetic responsiveness of a given superconductor to external electromagnetic excitations. With order parameter varying on the short scale of the coherence length, and the magnetic field being long-range, the numerical handling of 3D simulations becomes extremely challenging and time-consuming for realistic samples. Here we show precisely how one can employ graphics-processing units (GPUs) for this type of calculations, and obtain physics answers of interest in a reasonable time-frame – with speedup of over 100x compared to best available CPU implementations of the theory on a 2563grid. (C) 2016 Elsevier Inc. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York | Editor | ||
Language | Wos | 000381585100010 | Publication Date | 2016-06-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-9991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.744 | Times cited | 4 | Open Access | |
Notes | ; This work was supported through research grants from Brazilian agencies CNPq (306719/2012-6, 140840/2016-8) and FACEPE (IBPG-0510-1.03/15), BOF-UA, and the Research Foundation-Flanders (FWO-Vlaanderen). ; | Approved | Most recent IF: 2.744 | ||
Call Number | UA @ lucian @ c:irua:137115 | Serial | 4354 | ||
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Author | Xiao, Y.M.; Xu, W.; Van Duppen, B.; Peeters, F.M. | ||||
Title | Infrared to terahertz optical conductivity of n-type and p-type monolayer MoS2 in the presence of Rashba spin-orbit coupling | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 155432 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the effect of Rashba spin-orbit coupling (SOC) on the optoelectronic properties of n- and p-type monolayer MoS2. The optical conductivity is calculated within the Kubo formalism. We find that the spin-flip transitions enabled by the Rashba SOC result in a wide absorption window in the optical spectrum. Furthermore, we evaluate the effects of the polarization direction of the radiation, temperature, carrier density, and the strength of the Rashba spin-orbit parameter on the optical conductivity. We find that the position, width, and shape of the absorption peak or absorption window can be tuned by varying these parameters. This study shows that monolayer MoS2 can be a promising tunable optical and optoelectronic material that is active in the infrared to terahertz spectral range. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000386097800003 | Publication Date | 2016-10-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 20 | Open Access | |
Notes | ; Y.M.X. acknowledges financial support from the China Scholarship Council (CSC). This work was also supported by the National Natural Science Foundation of China (Grant No. 11574319), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. B.V.D. is supported by a Ph.D. fellowship from the Flemish Science Foundation. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:138175 | Serial | 4355 | ||
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Author | Yagmurcukardes, M.; Senger, R.T.; Peeters, F.M.; Sahin, H. | ||||
Title | Mechanical properties of monolayer GaS and GaSe crystals | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 245407 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The mechanical properties of monolayer GaS and GaSe crystals are investigated in terms of their elastic constants: in-plane stiffness (C), Poisson ratio (nu), and ultimate strength (sigma(U)) by means of first-principles calculations. The calculated elastic constants are compared with those of graphene and monolayer MoS2. Our results indicate that monolayer GaS is a stiffer material than monolayer GaSe crystals due to the more ionic character of the Ga-S bonds than the Ga-Se bonds. Although their Poisson ratio values are very close to each other, 0.26 and 0.25 for GaS and GaSe, respectively, monolayer GaS is a stronger material than monolayer GaSe due to its slightly higher sU value. However, GaS and GaSe crystals are found to be more ductile and flexible materials than graphene and MoS2. We have also analyzed the band-gap response of GaS and GaSe monolayers to biaxial tensile strain and predicted a semiconductor-metal crossover after 17% and 14% applied strain, respectively, for monolayer GaS and GaSe. In addition, we investigated how the mechanical properties are affected by charging. We found that the flexibility of single layer GaS and GaSe displays a sharp increase under 0.1e/cell charging due to the repulsive interactions between extra charges located on chalcogen atoms. These charging-controllable mechanical properties of single layers of GaS and GaSe can be of potential use for electromechanical applications. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000389503400008 | Publication Date | 2016-12-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 108 | Open Access | |
Notes | ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through project 114F397. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:139229 | Serial | 4356 | ||
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Author | Fatima; Oguz, I.C.; Çakir, D.; Hossain, S.; Mohottige, R.; Gulseren, O.; Oncel, N. | ||||
Title | On the structural and electronic properties of Ir-silicide nanowires on Si(001) surface | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 120 | Issue | 120 | Pages | 095303 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Iridium (Ir) modified Silicon (Si) (001) surface is studied with Scanning Tunneling Microscopy/Spectroscopy (STM/STS) and Density Functional Theory (DFT). A model for Ir-silicide nanowires based on STM images and ab-initio calculations is proposed. According to our model, the Ir adatom is on the top of the substrate dimer row and directly binds to the dimer atoms. I-V curves measured at 77K shows that the nanowires are metallic. DFT calculations confirm strong metallic nature of the nanowires. Published by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000383978100030 | Publication Date | 2016-09-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 7 | Open Access | |
Notes | ; We gratefully acknowledge the NSF (Grant No. DMR-1306101) for financial support. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ lucian @ c:irua:137132 | Serial | 4359 | ||
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Author | Khoeini, F.; Shakouri; Peeters, F.M. | ||||
Title | Peculiar half-metallic state in zigzag nanoribbons of MoS2 : spin filtering | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 125412 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Layered structures of molybdenum disulfide (MoS2) belong to a new class of two-dimensional (2D) semiconductor materials in which monolayers exhibit a direct band gap in their electronic spectrum. This band gap has recently been shown to vanish due to the presence of metallic edge modes when MoS2 monolayers are terminated by zigzag edges on both sides. Here, we demonstrate that a zigzag nanoribbon of MoS2, when exposed to an external exchange field in combination with a transverse electric field, has the potential to exhibit a peculiar half-metallic nature and thereby allows electrons of only one spin direction to move. The peculiarity of such spin-selective conductors originates from a spin switch near the gap-closing region, so the allowed spin orientation can be controlled by means of an external gate voltage. It is shown that the induced half-metallic phase is resistant to random fluctuations of the exchange field as well as the presence of edge vacancies. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000383238800009 | Publication Date | 2016-09-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 38 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:137130 | Serial | 4360 | ||
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Author | Van der Donck, M.; De Beule, C.; Partoens, B.; Peeters, F.M.; Van Duppen, B. | ||||
Title | Piezoelectricity in asymmetrically strained bilayer graphene | Type | A1 Journal article | ||
Year | 2016 | Publication | 2D materials | Abbreviated Journal | 2D Mater |
Volume | 3 | Issue | 3 | Pages | 035015 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We study the electronic properties of commensurate faulted bilayer graphene by diagonalizing the one-particle Hamiltonian of the bilayer system in a complete basis of Bloch states of the individual graphene layers. Our novel approach is very general and can be easily extended to any commensurate graphene-based heterostructure. Here, we consider three cases: (i) twisted bilayer graphene, (ii) bilayer graphene where triaxial stress is applied to one layer and (iii) bilayer graphene where uniaxial stress is applied to one layer. We show that the resulting superstructures can be divided into distinct classes, depending on the twist angle or the magnitude of the induced strain. The different classes are distinguished from each other by the interlayer coupling mechanism, resulting in fundamentally different low-energy physics. For the cases of triaxial and uniaxial stress, the individual graphene layers tend to decouple and we find significant charge transfer between the layers. In addition, this piezoelectric effect can be tuned by applying a perpendicular electric field. Finally, we show how our approach can be generalized to multilayer systems. | ||||
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Corporate Author | Thesis | ||||
Publisher | IOP Publishing | Place of Publication | Bristol | Editor | |
Language | Wos | 000384072500003 | Publication Date | 2016-08-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2053-1583 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.937 | Times cited | 10 | Open Access | |
Notes | ; This work was supported by the Research Foundation-Flanders (FWO-Vl) through aspirant research grants to MVDD, CDB, and BVD. ; | Approved | Most recent IF: 6.937 | ||
Call Number | UA @ lucian @ c:irua:137203 | Serial | 4361 | ||
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Author | Callewaert, V.; Shastry, K.; Saniz, R.; Makkonen, I.; Barbiellini, B.; Assaf, B.A.; Heiman, D.; Moodera, J.S.; Partoens, B.; Bansil, A.; Weiss, A.H.; | ||||
Title | Positron surface state as a spectroscopic probe for characterizing surfaces of topological insulator materials | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 115411 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Topological insulators are attracting considerable interest due to their potential for technological applications and as platforms for exploring wide-ranging fundamental science questions. In order to exploit, fine-tune, control, and manipulate the topological surface states, spectroscopic tools which can effectively probe their properties are of key importance. Here, we demonstrate that positrons provide a sensitive probe for topological states and that the associated annihilation spectrum provides a technique for characterizing these states. Firm experimental evidence for the existence of a positron surface state near Bi2Te2Se with a binding energy of E-b = 2.7 +/- 0.2 eV is presented and is confirmed by first-principles calculations. Additionally, the simulations predict a significant signal originating from annihilation with the topological surface states and show the feasibility to detect their spin texture through the use of spin-polarized positron beams. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000383232800012 | Publication Date | 2016-09-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 15 | Open Access | |
Notes | ; I.M. acknowledges discussions with M. Ervasti and A. Harju. V.C. and R.S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. The computational resources and services used in this paper were, in part, provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government (EWI Department). I.M. acknowledges financial support from the Academy of Finland (Projects No. 285809 and No. 293932). The work at Northeastern University was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences Grant No. DE-FG02-07ER46352 and benefited from Northeastern University's Advanced Scientific Computation Center (ASCC) and the NERSC supercomputing center through DOE Grant No. DE-AC02-05CH11231. K.S. and A.W. acknowledge financial support from the National Science Foundation through Grants No. DMR-MRI-1338130 and No. DMR-1508719. D.H. received financial support from the National Science Foundation (Grant No. ECCS-1402738). J.S.M. was supported by the STC Center for Integrated Quantum Materials under NSF Grants No. DMR-1231319, No. DMR-1207469, and ONR Grant No. N00014-13-1-0301. B.A.A. also acknowledges support from the LabEx ENS-ICFP Grant No. ANR-10-LABX-0010/ANR-10-IDEX-0001-02 PSL. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:137134 | Serial | 4362 | ||
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Author | Yagmurcukardes, M.; Torun, E.; Senger, R.T.; Peeters, F.M.; Sahin, H. | ||||
Title | Mg(OH)2-WS2 van der Waals heterobilayer : electric field tunable band-gap crossover | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 195403 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Magnesium hydroxide [Mg(OH)(2)] has a layered brucitelike structure in its bulk form and was recently isolated as a new member of two-dimensional monolayer materials. We investigated the electronic and optical properties of monolayer crystals of Mg(OH)(2) and WS2 and their possible heterobilayer structure by means of first-principles calculations. It was found that both monolayers of Mg(OH)(2) and WS2 are direct-gap semiconductors and these two monolayers form a typical van der Waals heterostructure with a weak interlayer interaction and a type-II band alignment with a staggered gap that spatially separates electrons and holes. We also showed that an out-of-plane electric field induces a transition from a staggered to a straddling-type heterojunction. Moreover, by solving the Bethe-Salpeter equation on top of single-shot G(0)W(0) calculations, we show that the low-energy spectrum of the heterobilayer is dominated by the intralyer excitons of the WS2 monolayer. Because of the staggered interfacial gap and the field-tunable energy-band structure, the Mg(OH)(2)-WS2 heterobilayer can become an important candidate for various optoelectronic device applications in nanoscale. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000386769400007 | Publication Date | 2016-11-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 38 | 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). H.S. is supported by a FWOPegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge support from TUBITAK through Project No. 114F397. H.S. acknowledges support from Bilim Akademisi – The Science Academy, Turkey, under the BAGEP program. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:138205 | Serial | 4364 | ||
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Author | Shumilin, A.V.; Baranov, V.V.; Kabanov, V.V. | ||||
Title | Upper critical field in the model with finite-range interaction between electrons | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 174506 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We develop a theory of the upper critical field in a BCS superconductor with a nonlocal interaction between electrons. We have shown that the nonlocal interaction is characterized by the parameter k(F)rho(0), where k(F) is the Fermi momentum and rho(0) is the radius of electron-electron interaction. The presence of the external magnetic field leads to the generation of additional components of the order parameter with different angular momenta. This effect leads to the enhancement of the upper critical field above the orbital limiting field. In addition the upward curvature in the temperature dependence of H-c2 (T) in the clean limit is predicted. The impurity scattering suppresses the effect in the dirty limit. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000387884100005 | Publication Date | 2016-11-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.836 | Times cited | Open Access | ||
Notes | ; ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:139166 | Serial | 4365 | ||
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Author | Eijt, S.W.H.; Shi, W.; Mannheim, A.; Butterling, M.; Schut, H.; Egger, W.; Dickmann, M.; Hugenschmidt, C.; Shakeri, B.; Meulenberg, R.W.; Callewaert, V.; Saniz, R.; Partoens, B.; Barbiellini, B.; Bansil, A.; Melskens, J.; Zeman, M.; Smets, A.H.M.; Kulbak, M.; Hodes, G.; Cahen, D.; Brück, E. | ||||
Title | New insights into the nanostructure of innovative thin film solar cells gained by positron annihilation spectroscopy | Type | A1 Journal article | ||
Year | 2017 | Publication | Journal of physics : conference series | Abbreviated Journal | |
Volume | 791 | Issue | 791 | Pages | 012021 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Recent studies showed that positron annihilation methods can provide key insights into the nanostructure and electronic structure of thin film solar cells. In this study, positron annihilation lifetime spectroscopy (PALS) is applied to investigate CdSe quantum dot (QD) light absorbing layers, providing evidence of positron trapping at the surfaces of the QDs. This enables one to monitor their surface composition and electronic structure. Further, 2D-Angular Correlation of Annihilation Radiation (2D-ACAR) is used to investigate the nanostructure of divacancies in photovoltaic-high-quality a-Si:H films. The collected momentum distributions were converted by Fourier transformation to the direct space representation of the electron-positron autocorrelation function. The evolution of the size of the divacancies as a function of hydrogen dilution during deposition of a-Si:H thin films was examined. Finally, we present a first positron Doppler Broadening of Annihilation Radiation (DBAR) study of the emerging class of highly efficient thin film solar cells based on perovskites. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000400610500021 | Publication Date | 2017-02-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1742-6588 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 1 | Open Access | ||
Notes | The work at Delft University of Technology was supported by the China Scholarship Council (CSC) grant of W.S., by ADEM, A green Deal in Energy Materials of the Ministry of Economic Affairs of The Netherlands (www.adem- innovationlab.nl), and the STW Vidi grant of A.S., Grant No. 10782. The PALS study is based upon experiments performed at the PLEPS instrument of the NEPOMUC facility at the Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany, and was supported by the European Commission under the 7 th Framework Programme, Key Action: Strengthening the European Research Area, Research Infrastructures, Contract No. 226507, NMI3. The work at University of Maine was supported by the National Science Foundation under Grant No. DMR-1206940. Research at the University of Antwerp was supported by FWO grants G022414N and G015013. The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University's Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. The work at the Weizmann Institute was supported by the Sidney E. Frank Foundation through the Israel Science Foundation, by the Israel Ministry of Science, and the Israel National Nano-Initiative. D.C. holds the Sylvia and Rowland Schaefer Chair in Energy Research. | Approved | Most recent IF: NA | ||
Call Number | CMT @ cmt @ c:irua:140850 | Serial | 4426 | ||
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Author | Fernández Becerra, V.; Milošević, M.V. | ||||
Title | Multichiral ground states in mesoscopic p-wave superconductors | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 184517 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using Ginzburg-Landau formalism, we investigate the effect of confinement on the ground state of mesoscopic chiral p-wave superconductors in the absence of magnetic field. We reveal stable multichiral states with domain walls separating the regions with different chiralities, as well as monochiral states with spontaneous currents flowing along the edges. We show that multichiral states can exhibit identifying signatures in the spatial profile of the magnetic field if those are not screened by edge currents in the case of strong confinement. Such magnetic detection of domain walls in topological superconductors can serve as long-sought evidence of broken time-reversal symmetry. Furthermore, when applying electric current to mesoscopic p-wave samples, we found a hysteretic behavior in the current-voltage characteristic that distinguishes states with and without domain walls, thereby providing another useful hallmark for indirect confirmation of chiral p-wave superconductivity. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000388816700001 | Publication Date | 2016-11-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 7 | Open Access | |
Notes | ; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen), the COST-EU action MP1201, and the MultiSuper network. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:139241 | Serial | 4456 | ||
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Author | Yagmurcukardes, M.; Peeters, F.M.; Senger, R.T.; Sahin, H. | ||||
Title | Nanoribbons: From fundamentals to state-of-the-art applications | Type | A1 Journal article | ||
Year | 2016 | Publication | Applied physics reviews | Abbreviated Journal | Appl Phys Rev |
Volume | 3 | Issue | 3 | Pages | 041302 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Atomically thin nanoribbons (NRs) have been at the forefront of materials science and nanoelectronics in recent years. State-of-the-art research on nanoscale materials has revealed that electronic, magnetic, phononic, and optical properties may differ dramatically when their one-dimensional forms are synthesized. The present article aims to review the recent advances in synthesis techniques and theoretical studies on NRs. The structure of the review is organized as follows: After a brief introduction to low dimensional materials, we review different experimental techniques for the synthesis of graphene nanoribbons (GNRs) with their advantages and disadvantages. In addition, theoretical investigations on width and edge-shape-dependent electronic and magnetic properties, functionalization effects, and quantum transport properties of GNRs are reviewed. We then devote time to the NRs of the transition metal dichalcogenides (TMDs) family. First, various synthesis techniques, E-field-tunable electronic and magnetic properties, and edge-dependent thermoelectric performance of NRs of MoS2 and WS2 are discussed. Then, strongly anisotropic properties, growth-dependent morphology, and the weakly width-dependent bandgap of ReS2 NRs are summarized. Next we discuss TMDs having a T-phase morphology such as TiSe2 and stable single layer NRs of mono-chalcogenides. Strong edge-type dependence on characteristics of GaS NRs, width-dependent Seebeck coefficient of SnSe NRs, and experimental analysis on the stability of ZnSe NRs are reviewed. We then focus on the most recently emerging NRs belonging to the class of transition metal trichalcogenides which provide ultra-high electron mobility and highly anisotropic quasi-1D properties. In addition, width-, edge-shape-, and functionalization-dependent electronic and mechanical properties of blackphosphorus, a monoatomic anisotropic material, and studies on NRs of group IV elements (silicene, germanene, and stanene) are reviewed. Observation of substrate-independent quantum well states, edge and width dependent properties, the topological phase of silicene NRs are reviewed. In addition, H-2 concentration-dependent transport properties and anisotropic dielectric function of GeNRs and electric field and strain sensitive I-V characteristics of SnNRs are reviewed. We review both experimental and theoretical studies on the NRs of group III-V compounds. While defect and N-termination dependent conductance are highlighted for boron nitride NRs, aluminum nitride NRs are of importance due to their dangling bond, electric field, and strain dependent electronic and magnetic properties. Finally, superlattice structure of NRs of GaN/AlN, Si/Ge, G/BN, and MoS2/WS2 is reviewed. Published by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | Amer inst physics | Place of Publication | Melville | Editor | |
Language | Wos | 000390443800013 | Publication Date | 2016-11-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1931-9401 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 13.667 | Times cited | 63 | Open Access | |
Notes | ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges the support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through Project No. 114F397. F.M.P. was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; | Approved | Most recent IF: 13.667 | ||
Call Number | UA @ lucian @ c:irua:140299 | Serial | 4457 | ||
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Author | Iyikanat, F.; Senger, R.T.; Peeters, F.M.; Sahin, H. | ||||
Title | Quantum-Transport Characteristics of a p-n Junction on Single-Layer TiS3 | Type | A1 Journal article | ||
Year | 2016 | Publication | ChemPhysChem : a European journal of chemical physics and physical chemistry | Abbreviated Journal | Chemphyschem |
Volume | 17 | Issue | 17 | Pages | 3985-3991 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By using density functional theory and non-equilibrium Green's function-based methods, we investigated the electronic and transport properties of a TiS3 monolayer p-n junction. We constructed a lateral p-n junction on a TiS3 monolayer using Li and F adatoms. An applied bias voltage caused significant variability in the electronic and transport properties of the TiS3 p-n junction. In addition, the spin-dependent current-volt-age characteristics of the constructed TiS3 p-n junction were analyzed. Important device characteristics were found, such as negative differential resistance and rectifying diode behaviors for spin-polarized currents in the TiS3 p-n junction. These prominent conduction properties of the TiS3 p-n junction offer remarkable opportunities for the design of nanoelectronic devices based on a recently synthesized single-layered material. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Weinheim | Editor | ||
Language | Wos | 000389534800018 | Publication Date | 2016-09-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1439-4235 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.075 | Times cited | 12 | Open Access | |
Notes | ; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and the Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). FI, HS, and RTS acknowledge the support from TUBITAK Project No 114F397. H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. ; | Approved | Most recent IF: 3.075 | ||
Call Number | UA @ lucian @ c:irua:140245 | Serial | 4458 | ||
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Author | Petrovic, M.D.; Peeters, F.M. | ||||
Title | Quantum transport in graphene Hall bars: Effects of vacancy disorder | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 94 | Issue | 94 | Pages | 235413 |
Keywords ![]() |
A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the tight-binding model, we investigate the influence of vacancy disorder on electrical transport in graphene Hall bars in the presence of quantizing magnetic fields. Disorder, induced by a random distribution of monovacancies, breaks the graphene sublattice symmetry and creates states localized on the vacancies. These states are observable in the bend resistance, as well as in the total DOS. Their energy is proportional to the square root of the magnetic field, while their localization length is proportional to the cyclotron radius. At the energies of these localized states, the electron current flows around the monovacancies and, as we show, it can follow unexpected paths depending on the particular arrangement of vacancies. We study how these localized states change with the vacancy concentration, and what are the effects of including the next-nearest-neighbor hopping term. Our results are also compared with the situation when double vacancies are present in the system. Double vacancies also induce localized states, but their energy and magnetic field dependencies are different. Their localization energy scales linearly with the magnetic field, and their localization length appears not to depend on the field strength. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000389574200005 | Publication Date | 2016-12-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 14 | Open Access | |
Notes | ; This work was supported by the Methusalem program of the Flemish government. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:140237 | Serial | 4459 | ||
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