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Author |
Zhao, H.J.; Wu, W.; Zhou, W.; Shi, Z.X.; Misko, V.R.; Peeters, F.M. |
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Title |
Reentrant dynamics of driven pancake vortices in layered superconductors |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
024514 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The dynamics of driven pancake vortices in layered superconductors is studied using molecular-dynamics simulations. We found that, with increasing driving force, for strong interlayer coupling, the preexisted vortex lines either directly depin or first transform to two-dimensional (2D) pinned states before they are depinned, depending on the pinning strength. In a narrow region of pinning strengths, we found an interesting repinning process, which results in a negative differential resistance. For weak interlayer coupling, individually pinned pancake vortices first form disordered 2D flow and then transform to ordered three-dimensional (3D) flow with increasing driving force. However, for extremely strong pinning, the random pinning-induced thermal-like Langevin forces melt 3D vortex lines, which results in a persistent 2D flow in the fast-sliding regime. In the intermediate regime, the peak effect is found: With increasing driving force, the moving pancake vortices first crystallize to moving 3D vortex lines, and then these 3D vortex lines are melted, leading to the appearance of a reentrant 2D flow state. Our results are summarized in a dynamical phase diagram. |
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Wos |
000380097800006 |
Publication Date |
2016-07-18 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
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Notes |
; We acknowledge useful discussions with C. Olson Reichhardt. This work was supported by the Natural Science Foundation of Jiangsu Province (Grant No. BK20150595), National Natural Science Foundation of China (Grants No. NSFC-U1432135 and No. 11611140101). V.R.M. acknowledges support from the “Odysseus” program of the Flemish Government and Flemish Science Foundation (FWO-Vl), the FWO-Vl, and the Research Fund of the University of Antwerp. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:134943 |
Serial |
4238 |
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Permanent link to this record |
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Author |
Missault, N.; Vasilopoulos, P.; Peeters, F.M.; Van Duppen, B. |
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Title |
Spin- and valley-dependent miniband structure and transport in silicene superlattices |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
93 |
Issue |
93 |
Pages |
125425 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate silicene superlattices in the presence of a tunable barrier potential U, an exchange field M, and a perpendicular electric field E-z. The resulting miniband structure depends on the spin and valley indices and on the fields M and E-z. These fields determine the minigaps and also affect the additional Dirac points brought about by the periodic potential U. In addition, we consider diffusive transport and assess its dependence on the spin and valley indices as well as on temperature. The corresponding spin and valley polarizations strongly depend on the potential U and can be made almost 100% at very low temperatures at particular values of the Fermi energy. |
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Wos |
000372715800009 |
Publication Date |
2016-03-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
49 |
Open Access |
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Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.), and by the Flemish Science Foundation FWO-Vl) with the “Odysseus” Program (N. M.) and with a PhD research grant (B.V.D.). ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:133194 |
Serial |
4246 |
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Permanent link to this record |
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Author |
Horzum, S.; Torun, E.; Serin, T.; Peeters, F.M. |
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Title |
Structural, electronic and optical properties of Cu-doped ZnO : experimental and theoretical investigation |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Philosophical magazine |
Abbreviated Journal |
Philos Mag |
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Volume |
96 |
Issue |
96 |
Pages |
1743-1756 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Experiments are supplemented with ab initio density functional theory (DFT) calculations in order to investigate how the structural, electronic and optical properties of zinc oxide (ZnO) thin films are modified upon Cu doping. Changes in characteristic properties of doped thin films, that are deposited on a glass substrate by sol-gel dip coating technique, are monitored using X-ray diffraction (XRD) and UV measurements. Our ab initio calculations show that the electronic structure of ZnO can be well described by DFT+U/G(0)W(0) method and we find that Cu atom substitutional doping in ZnO is the most favourable case. Our XRD measurements reveal that the crystallite size of the films decrease with increasing Cu doping. Moreover, we determine the optical constants such as refractive index, extinction coefficient, optical dielectric function and optical energy band gap values of the films by means of UV-Vis transmittance spectra. The optical band gap of ZnO the thin film linearly decreases from 3.25 to 3.20 eV at 5% doping. In addition, our calculations reveal that the electronic defect states that stem from Cu atoms are not optically active and the optical band gap is determined by the ZnO band edges. Experimentally observed structural and optical results are in good agreement with our theoretical results. |
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Wos |
000376076500002 |
Publication Date |
2016-05-07 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1478-6435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.505 |
Times cited |
29 |
Open Access |
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Notes |
; Theoretical part of 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. Experimental part of this work was supported by Ankara University BAP under Project Number [14B0443001]. ; |
Approved |
Most recent IF: 1.505 |
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Call Number |
UA @ lucian @ c:irua:134161 |
Serial |
4254 |
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Permanent link to this record |
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Author |
Chaves, A.; Mayers, M.Z.; Peeters, F.M.; Reichman, D.R. |
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Title |
Theoretical investigation of electron-hole complexes in anisotropic two-dimensional materials |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
93 |
Issue |
93 |
Pages |
115314 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Trions and biexcitons in anisotropic two-dimensional materials are investigated within an effective mass theory. Explicit results are obtained for phosphorene and arsenene, materials that share features such as a direct quasiparticle gap and anisotropic conduction and valence bands. Trions are predicted to have remarkably high binding energies and an elongated electron-hole structure with a preference for alignment along the armchair direction, where the effective masses are lower. We find that biexciton binding energies are also notably large, especially for monolayer phosphorene, where they are found to be twice as large as those for typical monolayer transition metal dichalcogenides. |
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Wos |
000372715700001 |
Publication Date |
2016-03-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
33 |
Open Access |
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Notes |
; This work has been financially supported by CNPq, through the PRONEX/FUNCAP and Science Without Borders programs, the FWO-CNPq bilateral program between Brazil and Flanders, and the Lemann Foundation. M.Z.M. is supported by a fellowship from the National Science Foundation, under Grant No. DGE-11-44155. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:133191 |
Serial |
4262 |
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Permanent link to this record |
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Author |
Van der Donck, M.; Peeters, F.M.; Van Duppen, B. |
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Title |
Transport properties of bilayer graphene in a strong in-plane magnetic field |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
93 |
Issue |
93 |
Pages |
115423 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000372409900006 |
Publication Date |
2016-03-21 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:133197 |
Serial |
4267 |
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Permanent link to this record |
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Author |
Grujić, M.M.; Ezawa, M.; Tadic, M.Z.; Peeters, F.M. |
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Title |
Tunable skewed edges in puckered structures |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
93 |
Issue |
93 |
Pages |
245413 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000377802700010 |
Publication Date |
2016-06-16 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
29 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:134599 |
Serial |
4268 |
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Permanent link to this record |
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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. |
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Title |
Uniform strain in heterostructure tunnel field-effect transistors |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
IEEE electron device letters |
Abbreviated Journal |
Ieee Electr Device L |
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Volume |
37 |
Issue |
37 |
Pages |
337-340 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000372372100026 |
Publication Date |
2016-01-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0741-3106 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.048 |
Times cited |
17 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:133207 |
Serial |
4271 |
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Permanent link to this record |
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Author |
Fernández Becerra, V.; Sardella, E.; Peeters, F.M.; Milošević, M.V. |
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Title |
Vortical versus skyrmionic states in mesoscopic p-wave superconductors |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
93 |
Issue |
93 |
Pages |
014518 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000369217400004 |
Publication Date |
2016-01-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:131581 |
Serial |
4275 |
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Permanent link to this record |
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Author |
Sisakht, E.T.; Fazileh, F.; Zare, M.H.; Zarenia, M.; Peeters, F.M. |
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Title |
Strain-induced topological phase transition in phosphorene and in phosphorene nanoribbons |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
085417 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000381600800004 |
Publication Date |
2016-08-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
76 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:135643 |
Serial |
4309 |
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Permanent link to this record |
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Author |
De Beule, C.; Ziani, N.T.; Zarenia, M.; Partoens, B.; Trauzettel, B. |
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Title |
Correlation and current anomalies in helical quantum dots |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
155111 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000385242200001 |
Publication Date |
2016-10-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:137234 |
Serial |
4351 |
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Permanent link to this record |
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Author |
Mirzakhani, M.; Zarenia, M.; da Costa, D.R.; Ketabi, S.A.; Peeters, F.M. |
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Title |
Energy levels of ABC-stacked trilayer graphene quantum dots with infinite-mass boundary conditions |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
165423 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000386168000011 |
Publication Date |
2016-10-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
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|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
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|
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 |
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Call Number |
UA @ lucian @ c:irua:138174 |
Serial |
4353 |
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Permanent link to this record |
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Author |
Xiao, Y.M.; Xu, W.; Van Duppen, B.; Peeters, F.M. |
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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 |
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|
Volume |
94 |
Issue |
94 |
Pages |
155432 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000386097800003 |
Publication Date |
2016-10-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
20 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:138175 |
Serial |
4355 |
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Permanent link to this record |
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Author |
Yagmurcukardes, M.; Senger, R.T.; Peeters, F.M.; Sahin, H. |
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Title |
Mechanical properties of monolayer GaS and GaSe crystals |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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|
Volume |
94 |
Issue |
94 |
Pages |
245407 |
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|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000389503400008 |
Publication Date |
2016-12-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
3.836 |
Times cited |
108 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:139229 |
Serial |
4356 |
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Permanent link to this record |
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Author |
Khoeini, F.; Shakouri; Peeters, F.M. |
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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 |
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Volume |
94 |
Issue |
94 |
Pages |
125412 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000383238800009 |
Publication Date |
2016-09-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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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 |
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Notes |
; ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:137130 |
Serial |
4360 |
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Permanent link to this record |
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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.; |
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Title |
Positron surface state as a spectroscopic probe for characterizing surfaces of topological insulator materials |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
115411 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000383232800012 |
Publication Date |
2016-09-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:137134 |
Serial |
4362 |
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Permanent link to this record |
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Author |
Yagmurcukardes, M.; Torun, E.; Senger, R.T.; Peeters, F.M.; Sahin, H. |
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Title |
Mg(OH)2-WS2 van der Waals heterobilayer : electric field tunable band-gap crossover |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
195403 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000386769400007 |
Publication Date |
2016-11-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
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Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
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|
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 |
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Call Number |
UA @ lucian @ c:irua:138205 |
Serial |
4364 |
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Permanent link to this record |
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Author |
Shumilin, A.V.; Baranov, V.V.; Kabanov, V.V. |
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Title |
Upper critical field in the model with finite-range interaction between electrons |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
174506 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Place of Publication |
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Language |
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Wos |
000387884100005 |
Publication Date |
2016-11-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.836 |
Times cited |
|
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:139166 |
Serial |
4365 |
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Permanent link to this record |
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Author |
Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Toniato, E.; Gombac, V.; Sada, C.; Turner, S.; Van Tendeloo, G.; Fornasiero, P.; |
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Title |
Iron-titanium oxide nanocomposites functionalized with gold particles : from design to solar hydrogen production |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
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Volume |
3 |
Issue |
3 |
Pages |
1600348 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Hematite-titania nanocomposites, eventually functionalized with gold nanoparticles (NPs), are designed and developed by a plasma-assisted strategy, consisting in: (i) the plasma enhanced-chemical vapor deposition of -Fe2O3 on fluorine-doped tin oxide substrates; the radio frequency-sputtering of (ii) TiO2, and (iii) Au in controlled amounts. A detailed chemicophysical characterization, carried out through a multitechnique approach, reveals that the target materials are composed by interwoven -Fe2O3 dendritic structures, possessing a high porosity and active area. TiO2 introduction results in the formation of an ultrathin titania layer uniformly covering Fe2O3, whereas Au sputtering yields a homogeneous dispersion of low-sized gold NPs. Due to the intimate and tailored interaction between the single constituents and their optical properties, the resulting composite materials are successfully exploited for solar-driven applications. In particular, promising photocatalytic performances in H-2 production by reforming of water-ethanol solutions under simulated solar illumination are obtained. The related insights, presented and discussed in this work, can yield useful guidelines to boost the performances of nanostructured photocatalysts for energy-related applications. |
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Place of Publication |
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Language |
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Wos |
000383783200021 |
Publication Date |
2016-07-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-7350; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.279 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.279 |
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Call Number |
UA @ lucian @ c:irua:137154 |
Serial |
4389 |
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Permanent link to this record |
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Author |
Van Havenbergh, K.; Turner, S.; Marx, N.; Van Tendeloo, G. |
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Title |
The mechanical behavior during (de)lithiation of coated silicon nanoparticles as anode material for lithium-ion batteries studied by InSitu transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Energy technology |
Abbreviated Journal |
Energy Technol-Ger |
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Volume |
4 |
Issue |
4 |
Pages |
1005-1012 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
One approach to cope with the continuous irreversible capacity loss in Si-based electrodes, attributed to lithiation-induced volume changes and the formation of a solid-electrolyte interface (SEI), is by coating silicon nanoparticles. A coating can improve the conductivity of the electrode, form a chemical shield against the electrolyte, or provide mechanical confinement to reduce the volume increase. The influence of such a coating on the mechanical behavior of silicon nanoparticles during Li insertion and Li extraction was investigated by insitu transmission electron microscopy. The type of coating was shown to influence the size of the unreacted core that remains after reaction of silicon with lithium. Furthermore, two mechanisms to relieve the stress generated during volume expansion are reported: the initiation of cracks and the formation of nanovoids. Both result in a full reaction of the silicon nanoparticles, whereas with the formation of cracks, additional surface area is created, on which an SEI can be formed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000382549500012 |
Publication Date |
2016-06-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2194-4296; 2194-4288 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.789 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:137167 |
Serial |
4406 |
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Permanent link to this record |
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Author |
Fernández Becerra, V.; Milošević, M.V. |
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Title |
Multichiral ground states in mesoscopic p-wave superconductors |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
184517 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000388816700001 |
Publication Date |
2016-11-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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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 |
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|
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 |
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Call Number |
UA @ lucian @ c:irua:139241 |
Serial |
4456 |
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Permanent link to this record |
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Author |
Petrovic, M.D.; Peeters, F.M. |
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Title |
Quantum transport in graphene Hall bars: Effects of vacancy disorder |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
235413 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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Wos |
000389574200005 |
Publication Date |
2016-12-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
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Notes |
; This work was supported by the Methusalem program of the Flemish government. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:140237 |
Serial |
4459 |
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Permanent link to this record |
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Author |
Sankaran, K.; Swerts, J.; Couet, S.; Stokbro, K.; Pourtois, G. |
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Title |
Oscillatory behavior of the tunnel magnetoresistance due to thickness variations in Ta vertical bar CoFe vertical bar MgO magnetic tunnel junctions : a first-principles study |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
094424 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
To investigate the impact of both the CoFe ferromagnetic layer thickness and the capping paramagnetic layer on the tunnel magnetoresistance (TMR), we performed first-principles simulations on epitaxial magnetic tunnel junctions contacted with either CoFe or Ta paramagnetic capping layers. We observed a strong oscillation of the TMR amplitude with respect to the thickness of the ferromagnetic layer. The TMR is found to be amplified whenever the MgO spin tunnel barrier is thickened. Quantization of the electronic structure of the ferromagnetic layers is found to be at the origin of this oscillatory behavior. Metals such as Ta contacting the magnetic layer are found to enhance the amplitude of the oscillations due to the occurrence of an interface dipole. The latter drives the band alignment and tunes the nature of the spin channels that are active during the tunneling process. Subsequently, the regular transmission spin channels are modulated in the magnetic tunnel junction stack and other complex ones are being activated. |
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Place of Publication |
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Wos |
000383860700004 |
Publication Date |
2016-09-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:137122 |
Serial |
4468 |
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Permanent link to this record |
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Author |
van den Broek, B.; Houssa, M.; Lu, A.; Pourtois, G.; Afanas'ev, V.; Stesmans, A. |
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Title |
Silicene nanoribbons on transition metal dichalcogenide substrates : effects on electronic structure and ballistic transport |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Nano Research |
Abbreviated Journal |
Nano Res |
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Volume |
9 |
Issue |
9 |
Pages |
3394-3406 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The idea of stacking multiple monolayers of different two-dimensional materials has become a global pursuit. In this work, a silicene armchair nanoribbon of width W and van der Waals-bonded to different transition-metal dichalcogenide (TMD) bilayer substrates MoX2 and WX2, where X = S, Se, Te is considered. The orbital resolved electronic structure and ballistic transport properties of these systems are simulated by employing van der Waals-corrected density functional theory and nonequilibrium Green's functions. We find that the lattice mismatch with the underlying substrate determines the electronic structure, correlated with the silicene buckling distortion and ultimately with the contact resistance of the two-terminal system. The smallest lattice mismatch, obtained with the MoTe2 substrate, results in the silicene ribbon properties coming close to those of a freestanding one. With the TMD bilayer acting as a dielectric layer, the electronic structure is tunable from a direct to an indirect semiconducting layer, and subsequently to a metallic electronic dispersion layer, with a moderate applied perpendicular electric field. |
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Place of Publication |
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Language |
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Wos |
000386770300018 |
Publication Date |
2016-08-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1998-0124 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.354 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 7.354 |
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Call Number |
UA @ lucian @ c:irua:138210 |
Serial |
4469 |
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Permanent link to this record |
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Author |
Ozkan, A. |
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Title |
CO2 splitting in a dielectric barrier discharge plasma : understanding of physical and chemical aspects |
Type |
Doctoral thesis |
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Year |
2016 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Publisher |
Université Libre de Bruxelles/Universiteit Antwerpen |
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Wos |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:136265 |
Serial |
4470 |
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Permanent link to this record |
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Author |
Heshmati-Moulai, A.; Simchi, H.; Esmaeilzadeh, M.; Peeters, F.M. |
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Title |
Phase transition and spin-resolved transport in MoS2 nanoribbons |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
94 |
Issue |
94 |
Pages |
235424 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The electronic structure and transport properties of monolayer MoS2 are studied using a tight-binding approach coupled with the nonequilibrium Green's function method. A zigzag nanoribbon of MoS2 is conducting due to the intersection of the edge states with the Fermi level that is located within the bulk gap. We show that applying a transverse electric field results in the disappearance of this intersection and turns the material into a semiconductor. By increasing the electric field the band gap undergoes a two stage linear increase after which it decreases and ultimately closes. It is shown that in the presence of a uniform exchange field, this electric field tuning of the gap can be exploited to open low energy domains where only one of the spin states contributes to the electronic conductance. This introduces possibilities in designing spin filters for spintronic applications. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000394546100005 |
Publication Date |
2016-12-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:141978 |
Serial |
4557 |
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Permanent link to this record |
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Author |
Becker, T.; Nelissen, K.; Cleuren, B.; Partoens, B.; Van den Broeck, C. |
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Title |
Comment on “Generalized exclusion processes : transport coefficients” |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical review E |
Abbreviated Journal |
Phys Rev E |
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Volume |
93 |
Issue |
93 |
Pages |
046101 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In a recent paper, Arita et al. [Phys. Rev. E 90, 052108 (2014)] consider the transport properties of a class of generalized exclusion processes. Analytical expressions for the transport-diffusion coefficient are derived by ignoring correlations. It is claimed that these expressions become exact in the hydrodynamic limit. In this Comment,we point out that (i) the influence of correlations upon the diffusion does not vanish in the hydrodynamic limit, and (ii) the expressions for the self- and transport diffusion derived by Arita et al. are special cases of results derived in Becker et al. [Phys. Rev. Lett. 111, 110601 (2013)]. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000374962100019 |
Publication Date |
2016-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2470-0045;2470-0053; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.366 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.366 |
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Call Number |
UA @ lucian @ c:irua:141060 |
Serial |
4591 |
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Permanent link to this record |
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Author |
Hoang, D.-Q.; Pobedinskas, P.; Nicley, S.S.; Turner, S.; Janssens, S.D.; Van Bael, M.K.; D'Haen, J.; Haenen, K. |
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Title |
Elucidation of the Growth Mechanism of Sputtered 2D Hexagonal Boron Nitride Nanowalls |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
16 |
Issue |
7 |
Pages |
3699-3708 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Hexagonal boron nitride nanowall thin films were deposited on Si(100) substrates using a Ar(51%)/N-2(44%)/H-2(5%) gas mixture by unbalanced radio frequency sputtering. The effects of various target-to-substrate distances, substrate temperatures, and substrate tilting angles were investigated. When the substrate is close to the target, hydrogen etching plays a significant role in the film growth, while the effect is negligible for films deposited at a farther distance. The relative quantity of defects was measured by a non-destructive infrared spectroscopy technique that characterized the hydrogen incorporation at dangling nitrogen bonds at defect sites in the deposited films. Despite the films deposited at different substrate tilting angles, the nanowalls of those films were found to consistently grow vertical to the substrate surface, independent of the tilting angle. This implies that chemical processes, rather than physical ones, govern the growth of the nanowalls. The results also reveal that the degree of nanowall crystallization is tunable by varying the growth parameters. Finally, evidence of hydrogen desorption during vacuum annealing is given based on measurements of infrared stretching (E-1u) and bending (A(2u)) modes of the optical phonons, and the H-N vibration mode. |
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Place of Publication |
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Language |
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Wos |
000379456700020 |
Publication Date |
2016-05-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.055 |
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Call Number |
UA @ lucian @ c:irua:144690 |
Serial |
4652 |
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Permanent link to this record |
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Author |
Sankaran, K.J.; Hoang, D.Q.; Srinivasu, K.; Korneychuk, S.; Turner, S.; Drijkoningen, S.; Pobedinskas, P.; Verbeeck, J.; Leou, K.C.; Lin, I.N.; Haenen, K. |
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Title |
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Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
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Volume |
213 |
Issue |
10 |
Pages |
2654-2661 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Utilization of Au and nanocrystalline diamond ( NCD) as interlayers noticeably modifies the microstructure and field electron emission ( FEE) properties of hexagonal boron nitride nanowalls ( hBNNWs) grown on Si substrates. The FEE properties of hBNNWs on Au could be turned on at a low turn-on field of 14.3V mu m(-1), attaining FEE current density of 2.58mAcm(-2) and life-time stability of 105 min. Transmission electron microscopy reveals that the Au-interlayer nucleates the hBN directly, preventing the formation of amorphous boron nitride ( aBN) in the interface, resulting in enhanced FEE properties. But Au forms as droplets on the Si substrate forming again aBN at the interface. Conversely, hBNNWs on NCD shows superior in life-time stability of 287 min although it possesses inferior FEE properties in terms of larger turn-on field and lower FEE current density as compared to that of hBNNWs-Au. The uniform and continuous NCD film on Si also circumvents the formation of aBN phases and allows hBN to grow directly on NCD. Incorporation of carbon in hBNNWs from the NCD-interlayer improves the conductivity of hBNNWs, which assists in transporting the electrons efficiently from NCD to hBNNWs that results in better field emission of electrons with high life-time stability. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000388321500017 |
Publication Date |
2016-09-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1862-6300 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.775 |
Times cited |
5 |
Open Access |
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Notes |
The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. K. J. Sankaran, P. Pobedinskas, and S. Turner are FWO Postdoctoral Fellows of the Research Foundations Flanders (FWO). |
Approved |
Most recent IF: 1.775 |
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Call Number |
UA @ lucian @ c:irua:144644UA @ admin @ c:irua:144644 |
Serial |
4655 |
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Permanent link to this record |
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Author |
Sankaran, K.J.; Duc Quang Hoang; Korneychuk, S.; Kunuku, S.; Thomas, J.P.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D'Haen, J.; Verbeeck, J.; Leou, K.-C.; Leung, K.T.; Lin, I.-N.; Haenen, K. |
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Title |
Hierarchical hexagonal boron nitride nanowall-diamond nanorod heterostructures with enhanced optoelectronic performance |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
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Volume |
6 |
Issue |
93 |
Pages |
90338-90346 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A superior field electron emission (FEE) source made from a hierarchical heterostructure, where two-dimensional hexagonal boron nitride (hBN) nanowalls were coated on one-dimensional diamond nanorods (DNRs), is fabricated using a simple and scalable method. FEE characteristics of hBN-DNR display a low turn-on field of 6.0 V mu m(-1), a high field enhancement factor of 5870 and a high life-time stability of 435 min. Such an enhancement in the FEE properties of hBN-DNR derives from the distinctive material combination, i.e., high aspect ratio of the heterostructure, good electron transport from the DNR to the hBN nanowalls and efficient field emission of electrons from the hBN nanowalls. The prospective application of these heterostructures is further evidenced by enhanced microplasma devices using hBN-DNR as a cathode, in which the threshold voltage was lowered to 350 V, affirming the role of hBN-DNR in the improvement of electron emission. |
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Place of Publication |
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Language |
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Wos |
000385451800044 |
Publication Date |
2016-09-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2046-2069 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.108 |
Times cited |
8 |
Open Access |
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Notes |
The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. KJ Sankaran, and P Pobedinskas are Postdoctoral Fellows of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 3.108 |
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Call Number |
UA @ lucian @ c:irua:144757UA @ admin @ c:irua:144757 |
Serial |
4662 |
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Permanent link to this record |
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Author |
Orlova, N.V.; Kuopanportti, P.; Milošević, M.V. |
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Title |
Skyrmionic vortex lattices in coherently coupled three-component Bose-Einstein condensates |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physical Review A |
Abbreviated Journal |
Phys Rev A |
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Volume |
94 |
Issue |
2 |
Pages |
023617 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We show numerically that a harmonically trapped and coherently Rabi-coupled three-component Bose-Einstein condensate can host unconventional vortex lattices in its rotating ground state. The discovered lattices incorporate square and zig-zag patterns, vortex dimers and chains, and doubly quantized vortices, and they can be quantitatively classified in terms of a skyrmionic topological index, which takes into account the multicomponent nature of the system. The exotic ground-state lattices arise due to the intricate interplay of the repulsive density-density interactions and the Rabi couplings as well as the ubiquitous phase frustration between the components. In the frustrated state, domain walls in the relative phases can persist between some components even at strong Rabi coupling, while vanishing between others. Consequently, in this limit the three-component condensate effectively approaches a two-component condensate with only density-density interactions. At intermediate Rabi coupling strengths, however, we face unique vortex physics that occurs neither in the two-component counterpart nor in the purely density-density-coupled three-component system. |
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Place of Publication |
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Language |
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Wos |
000381303800006 |
Publication Date |
2016-08-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9926;2469-9934; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.925 |
Times cited |
16 |
Open Access |
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Notes |
; This work was supported by the Research Foundation Flanders (FWO). P. K. acknowledges financial support from the Emil Aaltonen Foundation, the Finnish Cultural Foundation, the Magnus Ehrnrooth Foundation, and the Technology Industries of Finland Centennial Foundation. The authors thank R. P. Anderson, E. Babaev, I. O. Cherednikov, V. R. Misko, T. P. Simula, and J. Tempere for useful comments and discussions. ; |
Approved |
Most recent IF: 2.925 |
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Call Number |
UA @ lucian @ c:irua:144673 |
Serial |
4688 |
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Permanent link to this record |