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Author |
Tadić, M.; Peeters, F.M.; Janssens, K.L.; Korkusinski, M.; Hawrylak, P. |
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Title |
Strain and band edges in single and coupled cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
92 |
Issue  |
10 |
Pages |
5819-5829 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A comparative study is made of the strain distribution in cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots as obtained from isotropic elasticity theory, the anisotropic continuum mechanical model, and from atomistic calculations. For the isotropic case, the recently proposed approach [J. H. Davies, J. Appl. Phys. 84, 1358 (1998)] is used, while the finite-element method, the valence force field method, and Stillinger-Weber potentials are employed to calculate the strain in anisotropic structures. We found that all four methods result in strain distributions of similar shapes, but with notable quantitative differences inside the dot and near the disk-matrix boundary. The variations of the diagonal strains with the height of the quantum dot, with fixed radius, as calculated from all models, are almost linear. Furthermore, the energies of the band edges in the two types of quantum dots are extracted from the multiband effective-mass theory by inserting the strain distributions as obtained by the four models. We demonstrated that all strain models produce effective potentials for the heavy and light holes which agree very well inside the dot. A negligible anisotropy of all normal strains in the (x,y) plane is found, which, providing the axial symmetry of the kinetic part of the multiband effective-mass Hamiltonian, justifies the use of the axial approximation. Strain propagation along the vertical direction is also considered with the aim to study the influence of strain on the electron coupling in stacks of quantum dots. We found that the interaction between the strain fields of the individual quantum dots makes the effective quantum wells for the electrons in the conduction band shallower, thereby counteracting the quantum mechanical coupling. (C) 2002 American Institute of Physics. |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
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Language |
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Wos |
000178987200036 |
Publication Date |
2002-11-07 |
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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 |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
73 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2002 IF: 2.281 |
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Call Number |
UA @ lucian @ c:irua:103327 |
Serial |
3164 |
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Author |
Verbist, G.; Smondyrev, M.A.; Peeters, F.M.; Devreese, J.T. |
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Title |
Strong-coupling analysis of large bipolarons in 2 and 3 dimensions |
Type |
A1 Journal article |
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Year |
1992 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
45 |
Issue |
10 |
Pages |
5262-5269 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
In the limit of strong electron-phonon coupling, we use either a Pekar-type or an oscillator wave function for the center-of-mass coordinate and either a Coulomb or an oscillator wave function for the relative coordinate, and are able to reproduce all the results from the literature for the large-bipolaron binding energy. Lower bounds are constructed for the critical ratio eta(c) of dielectric constants below which bipolarons can exist. It is found that, in the strong-coupling limit, the stability region for bipolaron formation is much larger in two dimensions (2D) than in 3D. We introduce a model that combines the averaging of the relative coordinate over the asymptotically best wave function with a path-integral treatment of the center-of-mass motion. The stability region for bipolaron formation is increased compared with the full path-integral treatment at large values of the coupling constant alpha. The critical values are alpha(c) almost-equal-to 9.3 in 3D and alpha(c) almost-equal-to 4.5 in 2D. Phase diagrams for the presented models are also obtained in both 2D and 3D. |
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Place of Publication |
Lancaster, Pa |
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Wos |
A1992HJ68900016 |
Publication Date |
2002-07-27 |
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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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.736 |
Times cited |
68 |
Open Access |
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Notes |
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Approved |
PHYSICS, APPLIED 28/145 Q1 # |
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Call Number |
UA @ lucian @ c:irua:103051 |
Serial |
3178 |
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Author |
Dzhurakhalov, A.A.; Peeters, F.M. |
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Title |
Structure and energetics of hydrogen chemisorbed on a single graphene layer to produce graphane |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
49 |
Issue |
10 |
Pages |
3258-3266 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Integrated Molecular Plant Physiology Research (IMPRES) |
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Abstract |
Chemisorption of hydrogen on graphene is studied using atomistic simulations with the second generation of reactive empirical bond order Brenner inter-atomic potential. The lowest energy adsorption sites and the most important metastable sites are determined. The H concentration is varied from a single H atom, to clusters of H atoms up to full coverage. We found that when two or more H atoms are present, the most stable configurations of H chemisorption on a single graphene layer are ortho hydrogen pairs adsorbed on one side or on both sides of the graphene sheet. The latter has the highest hydrogen binding energy. The next stable configuration is the orthopara pair combination, and then para hydrogen pairs. The structural changes of graphene caused by chemisorbed hydrogen are discussed and are compared with existing experimental data and other theoretical calculations. The obtained results will be useful for nanoengineering of graphene by hydrogenation and for hydrogen storage. |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000291959300014 |
Publication Date |
2011-04-15 |
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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 |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.337 |
Times cited |
46 |
Open Access |
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Notes |
; A.D. thanks M.W. Zhao for a useful correspondence. This work was supported by the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
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Call Number |
UA @ lucian @ c:irua:90877 |
Serial |
3275 |
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Author |
Vodolazov, D.Y.; Peeters, F.M. |
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Title |
Symmetric and asymmetric states in a mesoscopic superconducting wire in the voltage-driven regime |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
75 |
Issue |
10 |
Pages |
104515,1-4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000245329100092 |
Publication Date |
2007-03-28 |
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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 |
1098-0121;1550-235X; |
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 |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2007 IF: 3.172 |
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Call Number |
UA @ lucian @ c:irua:64274 |
Serial |
3400 |
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Author |
Michel, K.H.; Verberck, B. |
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Title |
Theory of the elastic constants of graphite and graphene |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
245 |
Issue |
10 |
Pages |
2177-2180 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Born's long wave method is used to study the elastic properties of graphite and graphene. Starting from an empirical force constant model derived from full inplane phonon dispersions of graphite [Mohr et al., Phys. Rev. B 76, 035439 (2007)] we calculate the tension coefficients of graphene. Extending the model by interplanar interactions, we calculate the elastic constants of graphite. The agreement of our theoretical values with inelastic x-ray scattering results on elastic constants of graphite [Bosak et al., Phys. Rev. B 75, 153408 (2007)] is very satisfactory. |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000260581800066 |
Publication Date |
2008-08-25 |
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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 |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
47 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2008 IF: 1.166 |
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Call Number |
UA @ lucian @ c:irua:75660 |
Serial |
3621 |
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Author |
Singh, S.K.; Srinivasan, S.G.; Neek-Amal, M.; Costamagna, S.; van Duin, A.C.T.; Peeters, F.M. |
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Title |
Thermal properties of fluorinated graphene |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
87 |
Issue |
10 |
Pages |
104114-104116 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Large-scale atomistic simulations using the reactive force field approach are implemented to investigate the thermomechanical properties of fluorinated graphene (FG). A set of parameters for the reactive force field potential optimized to reproduce key quantum mechanical properties of relevant carbon-fluorine cluster systems are presented. Molecular dynamics simulations are used to investigate the thermal rippling behavior of FG and its mechanical properties and compare them with graphene, graphane and a sheet of boron nitride. The mean square value of the height fluctuations < h(2)> and the height-height correlation function H(q) for different system sizes and temperatures show that FG is an unrippled system in contrast to the thermal rippling behavior of graphene. The effective Young's modulus of a flake of fluorinated graphene is obtained to be 273 N/m and 250 N/m for a flake of FG under uniaxial strain along armchair and zigzag directions, respectively. DOI: 10.1103/PhysRevB.87.104114 |
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Place of Publication |
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Wos |
000316933500002 |
Publication Date |
2013-03-29 |
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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 |
1098-0121;1550-235X; |
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 |
80 |
Open Access |
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Notes |
; M.N.-A. is supported by the EU-Marie Curie IIF postdoc Fellowship/299855. This work is supported by the ESF-Eurographene project CONGRAN, the Flemish Science Foundation (FWO-Vl), and the Methusalem Foundation of the Flemish Government. S. G. S. and A.C.T.vD. acknowledge support by the Air Force Office of Scientific Research (AFOSR) under Grant No. FA9550-10-1-0563. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
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Call Number |
UA @ lucian @ c:irua:108495 |
Serial |
3629 |
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Author |
Zhang, L.-F.; Covaci, L.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M. |
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Title |
Unconventional vortex states in nanoscale superconductors due to shape-induced resonances in the inhomogeneous Cooper-pair condensate |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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Volume |
109 |
Issue |
10 |
Pages |
107001 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Vortex matter in mesoscopic superconductors is known to be strongly affected by the geometry of the sample. Here we show that in nanoscale superconductors with coherence length comparable to the Fermi wavelength the shape resonances of the order parameter results in an additional contribution to the quantum topological confinement-leading to unconventional vortex configurations. Our Bogoliubov-de Gennes calculations in a square geometry reveal a plethora of asymmetric, giant multivortex, and vortex-antivortex structures, stable over a wide range of parameters and which are very different from those predicted by the Ginzburg-Landau theory. These unconventional states are relevant for high-T-c nanograins, confined Bose-Einstein condensates, and graphene flakes with proximity-induced superconductivity. |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000308295700014 |
Publication Date |
2012-09-05 |
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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 |
0031-9007;1079-7114; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.462 |
Times cited |
31 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen). ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
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Call Number |
UA @ lucian @ c:irua:101850 |
Serial |
3801 |
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Author |
Doria, M.M.; Romaguera, A.R. de C.; Peeters, F.M. |
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Title |
Vortex patterns in a mesoscopic superconducting rod with a magnetic dot |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
81 |
Issue |
10 |
Pages |
104529,1-104529,11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study a mesoscopic superconducting rod with a magnetic dot on its top having its moment oriented along the axis of symmetry. We study the dependence of the vortex pattern with the height and find that for very short and very long rods, the vortex pattern acquires a simple structure, consisting of giant and of multivortex states, respectively. In the long limit, the most stable configuration consists of two vortices, that reach the lateral surface of the rod diametrically opposed. The long rod shows reentrant behavior within some range of its radius and of the dots magnetic moment. Our results are obtained within the Ginzburg-Landau approach in the limit of no magnetic shielding. |
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Place of Publication |
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Language |
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Wos |
000276248700123 |
Publication Date |
2010-03-31 |
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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 |
1098-0121;1550-235X; |
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 |
5 |
Open Access |
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Notes |
; The three authors acknowledge CNPq and the bilateral program between Brazil and Flanders for financial support. They also make the following acknowledgments for financial support: A. R. de C. Romaguera to FACEPE, M. M. Doria to FAPERJ, and F. M. Peeters to the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IUAP), and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:82272 |
Serial |
3877 |
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Author |
Liu, C.-Y.; Berdiyorov, G.R.; Milošević, M.V. |
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Title |
Vortex states in layered mesoscopic superconductors |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
83 |
Issue |
10 |
Pages |
104524-104524,10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Within the Ginzburg-Landau theory, we study the vortex structures in three-dimensional anisotropic mesoscopic superconductors in the presence of a uniform magnetic field. Anisotropy is included through varied Tc in different layers of the sample and leads to distinct differences in the vortex states and their free energy. Several unconventional states are found, some comprising vortex clusters or exhibiting asymmetry. In a tilted magnetic field, we found second-order transitions between different vortex states, although vortex entry is generally a first-order transition in mesoscopic samples. In multilayered samples the kinked vortex strings are formed owing to the competing interactions of vortices with Meissner currents and the weak-link boundaries. The length and deformation of vortex fragments are determined solely by the inclination and strength of applied magnetic field, and this lock-in does not depend on the degree of anisotropy between the superconducting layers. |
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Place of Publication |
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Language |
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Wos |
000288998200003 |
Publication Date |
2011-03-31 |
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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 |
1098-0121;1550-235X; |
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 |
22 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:89375 |
Serial |
3888 |
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Author |
Zhao, H.J.; Misko, V.R.; Peeters, F.M.; Oboznov, V.; Dubonos, S.V.; Grigorieva, I.V. |
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Title |
Vortex states in mesoscopic superconducting squares: formation of vortex shells |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
78 |
Issue |
10 |
Pages |
104517 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We analyze theoretically and experimentally vortex configurations in mesoscopic superconducting squares. Our theoretical approach is based on the analytical solution of the London equation using Green's-function method. The potential-energy landscape found for each vortex configuration is then used in Langevin-type molecular-dynamics simulations to obtain stable vortex configurations. Metastable states and transitions between them and the ground state are analyzed. We present our results of the first direct visualization of vortex patterns in micrometer-sized Nb squares, using the Bitter decoration technique. We show that the filling rules for vortices in squares with increasing applied magnetic field can be formulated, although in a different manner than in disks, in terms of formation of vortex “shells”. |
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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 |
000259690400093 |
Publication Date |
2008-09-18 |
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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 |
1098-0121;1550-235X; |
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 |
39 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
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Call Number |
UA @ lucian @ c:irua:102608 |
Serial |
3890 |
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Author |
Hawrylak, P.; Peeters, F.; Ensslin, K. |
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Title |
Carbononics : integrating electronics, photonics and spintronics with graphene quantum dots Preface |
Type |
Editorial |
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Year |
2016 |
Publication |
Physica status solidi: rapid research letters |
Abbreviated Journal |
Phys Status Solidi-R |
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Volume |
10 |
Issue |
10 |
Pages |
11-12 |
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Keywords |
Editorial; Condensed Matter Theory (CMT) |
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Abstract |
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Publisher |
Wiley-v c h verlag gmbh |
Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000368814500002 |
Publication Date |
2016-01-20 |
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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 |
1862-6254 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.032 |
Times cited |
7 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.032 |
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Call Number |
UA @ lucian @ c:irua:131600 |
Serial |
4146 |
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Author |
Schouteden, K.; Govaerts, K.; Debehets, J.; Thupakula, U.; Chen, T.; Li, Z.; Netsou, A.; Song, F.; Lamoen, D.; Van Haesendonck, C.; Partoens, B.; Park, K. |
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Title |
Annealing-Induced Bi Bilayer on Bi2Te3 Investigated via Quasi-Particle-Interference Mapping |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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| |
Volume |
10 |
Issue |
10 |
Pages |
8778-8787 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Topological insulators (TIs) are renowned for their exotic topological surface states (TSSs) that reside in the top atomic layers, and hence, detailed knowledge of the surface top atomic layers is of utmost importance. Here we present the remarkable morphology changes of Bi2Te3 surfaces, which have been freshly cleaved in air, upon subsequent systematic annealing in ultrahigh vacuum and the resulting effects on the local and area-averaging electronic properties of the surface states, which are investigated by combining scanning tunneling microscopy (STM), scanning tunneling spectroscopy (STS), and Auger electron spectroscopy (AES) experiments with density functional theory (DFT) calculations. Our findings demonstrate that the annealing induces the formation of a Bi bilayer atop the Bi2Te3 surface. The adlayer results in n-type doping, and the atomic defects act as scattering centers of the TSS electrons. We also investigated the annealing-induced Bi bilayer surface on Bi2Te3 via voltage-dependent quasi-particle-interference (QPI) mapping of the surface local density of states and via comparison with the calculated constant-energy contours and QPI patterns. We observed closed hexagonal patterns in the Fourier transform of real-space QPI maps with secondary outer spikes. DFT calculations attribute these complex QPI patterns to the appearance of a “second” cone due to the surface charge transfer between the Bi bilayer and the Bi2Te3. Annealing in ultrahigh vacuum offers a facile route for tuning of the topological properties and may yield similar results for other topological materials. |
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Address |
Department of Physics, Virginia Tech , Blacksburg, Virginia 24061, United States |
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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 |
English |
Wos |
000384399300073 |
Publication Date |
2016-09-02 |
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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 |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
15 |
Open Access |
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Notes |
The research in Leuven and Antwerp was supported by the Research FoundationFlanders (FWO, Belgium). The research in Leuven received additional support from the Flemish Concerted Research Action Program (BOF KULeuven, Project GOA/14/007) and the KULeuven Project GOA “Fundamental Challenges in Semiconductor Research”. Z.L. acknowledges the support from the China Scholarship Council (2011624021) and from KU Leuven Internal Funds (PDM). K.S. and J.D. acknowledge additional support from the FWO. T.C. and F.S. acknowledge the financial support of the National Key Projects for Basic Research of China (Grants 2013CB922103 and 2011CB922103), the National NaturalScience Foundation of China (Grant s 91421109, 11134005,11522432, and 11274003), the Natural Science Foundation ofJiangsu Province (Grant BK20130054), and the FundamentalResearch Funds for the Central Universities. K.P. wassupported by the U.S. National Science Foundation (DMR-1206354) and San Diego Supercomputer Center (SDSC)Comet and Gordon (DMR060009N). |
Approved |
Most recent IF: 13.942 |
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Call Number |
EMAT @ emat @ c:irua:136269 |
Serial |
4294 |
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| Permanent link to this record |
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Author |
Li, L.; Leenaerts, O.; Kong, X.; Chen, X.; Zhao, M.; Peeters, F.M. |
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Title |
Gallium bismuth halide GaBi-X2 (X = I, Br, Cl) monolayers with distorted hexagonal framework: Novel room-temperature quantum spin Hall insulators |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Nano Research |
Abbreviated Journal |
Nano Res |
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| |
Volume |
10 |
Issue |
10 |
Pages |
2168-2180 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Quantum spin Hall (QSH) insulators with a large topologically nontrivial bulk gap are crucial for future applications of the QSH effect. Among these, group III-V monolayers and their halides, which have a chair structure (regular hexagonal framework), have been widely studied. Using first-principles calculations, we formulate a new structure model for the functionalized group III-V monolayers, which consist of rectangular GaBi-X-2 (X = I, Br, Cl) monolayers with a distorted hexagonal framework (DHF). These structures have a far lower energy than the GaBi-X-2 monolayers with a chair structure. Remarkably, the DHF GaBi-X-2 monolayers are all QSH insulators, which exhibit sizeable nontrivial band gaps ranging from 0.17 to 0.39 eV. The band gaps can be widely tuned by applying different spin-orbit coupling strengths, resulting in a distorted Dirac cone. |
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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 |
000401320700029 |
Publication Date |
2017-04-08 |
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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 |
15 |
Open Access |
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Notes |
; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 7.354 |
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Call Number |
UA @ lucian @ c:irua:143739 |
Serial |
4598 |
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Author |
Zhang, L.-F.; Flammia, L.; Covaci, L.; Perali, A.; Milošević, M.V. |
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Title |
Multifaceted impact of a surface step on superconductivity in atomically thin films |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
96 |
Issue |
10 |
Pages |
104509 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Recent experiments show that an atomic step on the surface of atomically thin metallic films can strongly affect electronic transport. Here we reveal multiple and versatile effects that such a surface step can have on superconductivity in ultrathin films. By solving the Bogoliubov-de Gennes equations self-consistently in this regime, where quantum confinement dominates the emergent physics, we show that the electronic structure is profoundly modified on the two sides of the step, as is the spatial distribution of the superconducting order parameter and its dependence on temperature and electronic gating. Furthermore, the surface step changes nontrivially the transport properties both in the proximity-induced superconducting pair correlations and the Josephson effect, depending on the step height. These results offer a new route to tailor superconducting circuits and design atomically thin heterojunctions made of one same material. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000411076000012 |
Publication Date |
2017-09-18 |
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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 |
2469-9969; 2469-9950 |
ISBN |
|
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 |
; This work was supported by the Research Foundation Flanders (FWO-Vlaanderen), the Special Research Funds of the University of Antwerp (TOPBOF project) and the Italian MIUR through the PRIN 2015 program (Contract No. 2015C5SEJJ001). ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ lucian @ c:irua:146750 |
Serial |
4790 |
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Author |
Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V. |
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Title |
Tunable Snell's law for spin waves in heterochiral magnetic films |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
97 |
Issue |
10 |
Pages |
104422 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Thin ferromagnetic films with an interfacially induced DMI exhibit nontrivial asymmetric dispersion relations that lead to unique and useful magnonic properties. Here we derive an analytical expression for the magnon propagation angle within the micromagnetic framework and show how the dispersion relation can be approximated with a comprehensible geometrical interpretation in the k space of the propagation of spin waves. We further explore the refraction of spin waves at DMI interfaces in heterochiral magnetic films, after deriving a generalized Snell's law tunable by an in-plane magnetic field, that yields analytical expressions for critical incident angles. The found asymmetric Brewster angles at interfaces of regions with different DMI strengths, adjustable by magnetic field, support the conclusion that heterochiral ferromagnetic structures are an ideal platform for versatile spin-wave guides. |
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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 |
000428238600006 |
Publication Date |
2018-03-26 |
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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 |
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 |
20 |
Open Access |
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Notes |
This work was supported by the Research Foundation- Flanders (FWO-Vlaanderen) through Project No. G098917N. |
Approved |
Most recent IF: 3.836 |
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Call Number |
CMT @ cmt @c:irua:150118UA @ admin @ c:irua:150118 |
Serial |
4915 |
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Author |
Menezes, R.M.; Mulkers, J.; de Souza Silva, C.C.; Milošević, M.V. |
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Title |
Deflection of ferromagnetic and antiferromagnetic skyrmions at heterochiral interfaces |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
99 |
Issue |
10 |
Pages |
104409 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Devising magnetic nanostructures with spatially heterogeneous Dzyaloshinskii-Moriya interaction (DMI) is a promising pathway toward advanced confinement and control of magnetic skyrmions in potential devices. Here we discuss theoretically how a skyrmion interacts with a heterochiral interface using micromagnetic simulations and analytic arguments. We show that a heterochiral interface deflects the trajectory of ferromagnetic (FM) skyrmions, and that the extent of such deflection is tuned by the applied spin-polarized current and the difference in DMI across the interface. Further, we show that this deflection is characteristic of the FM skyrmion, and it is completely absent in the antiferromagnetic (AFM) case. In turn, we reveal that the AFM skyrmion achieves much higher velocities than its FM counterpart, yet experiences far stronger confinement in nanoengineered heterochiral tracks, which reinforces AFM skyrmions as a favorable choice for skyrmion-based devices. |
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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 |
000460720600005 |
Publication Date |
2019-03-07 |
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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 |
2469-9969; 2469-9950 |
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 |
19 |
Open Access |
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Notes |
; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen) and Brazilian Agencies FACEPE under Grant No. APQ-0198-1.05/14, CAPES and CNPq. ; |
Approved |
Most recent IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:158557 |
Serial |
5203 |
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Author |
Mogg, L.; Hao, G.-P.; Zhang, S.; Bacaksiz, C.; Zou, Y.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
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Title |
Atomically thin micas as proton-conducting membranes |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
14 |
Issue |
10 |
Pages |
962-+ |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Monolayers of graphene and hexagonal boron nitride (hBN) are highly permeable to thermal protons1,2. For thicker two-dimensional (2D) materials, proton conductivity diminishes exponentially, so that, for example, monolayer MoS2 that is just three atoms thick is completely impermeable to protons1. This seemed to suggest that only one-atom-thick crystals could be used as proton-conducting membranes. Here, we show that few-layer micas that are rather thick on the atomic scale become excellent proton conductors if native cations are ion-exchanged for protons. Their areal conductivity exceeds that of graphene and hBN by one to two orders of magnitude. Importantly, ion-exchanged 2D micas exhibit this high conductivity inside the infamous gap for proton-conducting materials3, which extends from ∼100 °C to 500 °C. Areal conductivity of proton-exchanged monolayer micas can reach above 100 S cm−2 at 500 °C, well above the current requirements for the industry roadmap4. We attribute the fast proton permeation to ~5-Å-wide tubular channels that perforate micas’ crystal structure, which, after ion exchange, contain only hydroxyl groups inside. Our work indicates that there could be other 2D crystals5 with similar nanometre-scale channels, which could help close the materials gap in proton-conducting applications. |
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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 |
000488977100016 |
Publication Date |
2019-09-02 |
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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 |
1748-3387; 1748-3395 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
38.986 |
Times cited |
37 |
Open Access |
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Notes |
; The work was supported by the Lloyd's Register Foundation, the Engineering and Physical Sciences Research Council (EPSRC)-EP/N010345/1, EP/M010619/1 and EP/ P009050/1, the European Research Council, the Graphene Flagship and the Royal Society. M.L.-H. acknowledges a Leverhulme Early Career Fellowship, G.-P.H. acknowledges a Marie Curie International Incoming Fellowship, and L.M. acknowledges the EPSRC NOWNano programme for funding. Y.Z. acknowledges the assistance of Eric Prestat in TEM specimen preparation. Computational resources were provided by the TUBITAK ULAKBIM High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; |
Approved |
Most recent IF: 38.986 |
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Call Number |
UA @ admin @ c:irua:163589 |
Serial |
5407 |
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Author |
Zhao, X.N.; Xu, W.; Xiao, Y.M.; Van Duppen, B. |
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Title |
Spin polarization in monolayer MoS₂ in the presence of proximity-induced interactions |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
International Journal Of Modern Physics C |
Abbreviated Journal |
Int J Mod Phys C |
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Volume |
31 |
Issue |
10 |
Pages |
2050143 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
When monolayer (ML) MoS2 is placed on a substrate, the proximity-induced interactions such as the Rashba spin-orbit coupling (RSOC) and exchange interaction (EI) can be introduced. Thus, the electronic system can behave like a spintronic device. In this study, we present a theoretical study on how the presence of the RSCO and EI can lead to the band splitting, the lifting of the valley degeneracy and to the spin polarization in n- and p-type ML MoS2. We find that the maxima of the in-plane spin orientation in the conduction and valence bands in ML MoS2 depend on the Rashba parameter and the effective Zeeman field factor. At a fixed Rashba parameter, the minima of the split conduction band and the maxima of the split valence band along with the spin polarization in ML MoS2 can be tuned effectively by varying the effective Zeeman field factor. On the basis that the EI can be induced by placing the ML MoS2 on a ferromagnetic substrate or by magnetic doping in ML MoS2, we predict that the interesting spintronic effects can be observed in n- and p-type ML MoS2. This work can be helpful to gain an in-depth understanding of the basic physical properties of ML MoS2 for application in advanced electronic and optoelectronic devices. |
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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 |
000583803200009 |
Publication Date |
2020-06-09 |
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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 |
0129-1831 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.9 |
Times cited |
|
Open Access |
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Notes |
; This work was supported by the 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. ; |
Approved |
Most recent IF: 1.9; 2020 IF: 1.171 |
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Call Number |
UA @ admin @ c:irua:173635 |
Serial |
6609 |
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Author |
Leishman, A.W.D.; Menezes, R.M.; Longbons, G.; Bauer, E.D.; Janoschek, M.; Honecker, D.; DeBeer-Schmitt, L.; White, J.S.; Sokolova, A.; Milošević, M.V.; Eskildsen, M.R. |
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Title |
Topological energy barrier for skyrmion lattice formation in MnSi |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
102 |
Issue |
10 |
Pages |
104416-104419 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report the direct measurement of the topological skyrmion energy barrier through a hysteresis of the skyrmion lattice in the chiral magnet MnSi. Measurements were made using small-angle neutron scattering with a custom-built resistive coil to allow for high-precision minor hysteresis loops. The experimental data were analyzed using an adapted Preisach model to quantify the energy barrier for skyrmion formation and corroborated by the minimum-energy path analysis based on atomistic spin simulations. We reveal that the skyrmion lattice in MnSi forms from the conical phase progressively in small domains, each of which consisting of hundreds of skyrmions, and with an activation barrier of several eV. |
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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 |
000568994800005 |
Publication Date |
2020-09-14 |
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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 |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
1 |
Open Access |
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Notes |
; This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Award No. DE-SC0005051 (A.W.D.L., G.L., M.R.E.), the Research Foundation -Flanders (FWO-Vlaanderen) (R.M.M., M.V.M.), and Brazilian Agencies FACEPE, CAPES and CNPq (R.M.M.). M.J. was supported by the LANL Directed Research and Development (LDRD) program via the Directed Research (DR) project “A New Approach to Mesoscale Functionality: Emergent Tunable Superlattices (20150082DR).” E.D.B. was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Science and Engineering, under project “Quantum Fluctuations in Narrow-Band Systems.” A portion of this research used resources at the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. Part of this work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institute, Villigen, Switzerland. We acknowledge useful conversations with E. Louden, D. Green, and A. Francisco in preparation for these experiments, as well as the assistance of K. Avers, G. Taufer, M. Harrington, M. Bartkowiak, and C. Baldwin in completing them. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:171959 |
Serial |
6631 |
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Author |
Lavor, I.R.; da Costa, D.R.; Covaci, L.; Milošević, M.V.; Peeters, F.M.; Chaves, A. |
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Title |
Zitterbewegung of moiré excitons in twisted MoS₂/WSe₂ heterobilayers |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Physical review letters |
Abbreviated Journal |
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Volume |
127 |
Issue |
10 |
Pages |
106801 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
The moire pattern observed in stacked noncommensurate crystal lattices, such as heterobilayers of transition metal dichalcogenides, produces a periodic modulation of their band gap. Excitons subjected to this potential landscape exhibit a band structure that gives rise to a quasiparticle dubbed the moire exciton. In the case of MoS2/WSe2 heterobilayers, the moire trapping potential has honeycomb symmetry and, consequently, the moire exciton band structure is the same as that of a Dirac-Weyl fermion, whose mass can be further tuned down to zero with a perpendicularly applied field. Here we show that, analogously to other Dirac-like particles, the moire exciton exhibits a trembling motion, also known as Zitterbewegung, whose long timescales are compatible with current experimental techniques for exciton dynamics. This promotes the study of the dynamics of moire excitons in van der Waals heterostructures as an advantageous solid-state platform to probe Zitterbewegung, broadly tunable by gating and interlayer twist angle. |
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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 |
000692200800020 |
Publication Date |
2021-08-31 |
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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 |
1079-7114 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
4 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:181599 |
Serial |
6896 |
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Author |
Pinto, N.; McNaughton, B.; Minicucci, M.; Milošević, M.V.; Perali, A. |
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| |
Title |
Electronic transport mechanisms correlated to structural properties of a reduced graphene oxide sponge |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
|
| |
Volume |
11 |
Issue |
10 |
Pages |
2503 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We report morpho-structural properties and charge conduction mechanisms of a foamy “graphene sponge ”, having a density as low as & AP;0.07 kg/m3 and a carbon to oxygen ratio C:O & SIME; 13:1. The spongy texture analysed by scanning electron microscopy is made of irregularly-shaped millimetres-sized small flakes, containing small crystallites with a typical size of & SIME;16.3 nm. A defect density as high as & SIME;2.6 x 1011 cm-2 has been estimated by the Raman intensity of D and G peaks, dominating the spectrum from room temperature down to & SIME;153 K. Despite the high C:O ratio, the graphene sponge exhibits an insulating electrical behavior, with a raise of the resistance value at & SIME;6 K up to 5 orders of magnitude with respect to the room temperature value. A variable range hopping (VRH) conduction, with a strong 2D character, dominates the charge carriers transport, from 300 K down to 20 K. At T < 20 K, graphene sponge resistance tends to saturate, suggesting a temperature-independent quantum tunnelling. The 2D-VRH conduction originates from structural disorder and is consistent with hopping of charge carriers between sp2 defects in the plane, where sp3 clusters related to oxygen functional groups act as potential barriers.</p> |
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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 |
000713174500001 |
Publication Date |
2021-09-28 |
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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 |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2079-4991 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
3.553 |
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 3.553 |
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| |
Call Number |
UA @ admin @ c:irua:184050 |
Serial |
6988 |
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| Permanent link to this record |
| |
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| |
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Author |
Bellizotti Souza, J.C.; Vizarim, N.P.; Reichhardt, C.J.O.; Reichhardt, C.; Venegas, P.A. |
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| |
Title |
Clogging, diode and collective effects of skyrmions in funnel geometries |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
|
| |
Volume |
24 |
Issue |
10 |
Pages |
103030-14 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Using a particle-based model, we examine the collective dynamics of skyrmions interacting with a funnel potential under dc driving as the skyrmion density and relative strength of the Magnus and damping terms are varied. For driving in the easy direction, we find that increasing the skyrmion density reduces the average skyrmion velocity due to jamming of skyrmions near the funnel opening, while the Magnus force causes skyrmions to accumulate on one side of the funnel array. For driving in the hard direction, there is a critical skyrmion density below which the skyrmions become trapped. Above this critical value, a clogging effect appears with multiple depinning and repinning states where the skyrmions can rearrange into different clogged configurations, while at higher drives, the velocity-force curves become continuous. When skyrmions pile up near the funnel opening, the effective size of the opening is reduced and the passage of other skyrmions is blocked by the repulsive skyrmion-skyrmion interactions. We observe a strong diode effect in which the critical depinning force is higher and the velocity response is smaller for hard direction driving. As the ratio of Magnus force to dissipative term is varied, the skyrmion velocity varies in a non-linear and non-monotonic way due to the pile up of skyrmions on one side of the funnels. At high Magnus forces, the clogging effect for hard direction driving is diminished. |
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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 |
000873333400001 |
Publication Date |
2022-10-04 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1367-2630 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.3 |
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 3.3 |
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| |
Call Number |
UA @ admin @ c:irua:192178 |
Serial |
7287 |
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| Permanent link to this record |
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| |
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Author |
Seyedmohammadzadeh, M.; Sevik, C.; Guelseren, O. |
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| |
Title |
Two-dimensional heterostructures formed by graphenelike ZnO and MgO monolayers for optoelectronic applications |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review materials |
Abbreviated Journal |
|
|
| |
Volume |
6 |
Issue |
10 |
Pages |
104004-104013 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Two-dimensional heterostructures are an emerging class of materials for novel applications because of extensive engineering potential by tailoring intriguing properties of different layers as well as the ones arising from their interface. A systematic investigation of mechanical, electronic, and optical properties of possible heterostructures formed by bilayer structures graphenelike ZnO and MgO monolayers is presented. Different functionality of each layer makes these heterostructures very appealing for device applications. ZnO layer is convenient for electron transport in these structures, while MgO layer improves electron collection. At the outset, all of the four possible stacking configurations across the heterostructure are mechanically stable. In addition, stability analysis using phonon dispersion reveals that the AB stacking formed by placing the Mg atom on top of the O atom of the ZnO layer is also dynamically stable at zero temperature. Henceforth, we have investigated the optical properties of these stable heterostructures by applying many-body perturbation theory within the framework of GW approximation and solving the Bethe-Salpeter equation. It is demonstrated that strong excitonic effects reduce the optical band gap to the visible light spectrum range. These results show that this new two-dimensional form of ZnO/MgO heterostructures open an avenue for novel optoelectronic device applications. |
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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 |
|
Wos |
000877514900005 |
Publication Date |
2022-10-24 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2475-9953 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.4 |
Times cited |
|
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 3.4 |
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| |
Call Number |
UA @ admin @ c:irua:192167 |
Serial |
7346 |
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| Permanent link to this record |
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| |
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Author |
Wang, J.; Zhao, W.-S.; Hu, Y.; Filho, R.N.C.; Peeters, F.M. |
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| |
Title |
Charged vacancy in graphene : interplay between Landau levels and atomic collapse resonances |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Physical review B |
Abbreviated Journal |
|
|
| |
Volume |
109 |
Issue |
10 |
Pages |
104103-104106 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The interplay between a magnetic field and the Coulomb potential from a charged vacancy on the electron states in graphene is investigated within the tight-binding model. The Coulomb potential removes locally Landau level degeneracy, while the vacancy introduces a satellite level next to the normal Landau level. These satellite levels are found throughout the positive-energy region, but in the negative-energy region, they turn into atomic collapse resonances. Crossings between Landau levels with different angular quantum number m are found. Unlike the point impurity system in which an anticrossing occurs between Landau levels of the same m, in this work anticrossing is found between the normal Landau level and the vacancy-induced level. The atomic collapse resonance hybridizes with the Landau levels. The charge at which the lowest Landau level m = -1, N = 1 crosses E = 0 increases with enhancing magnetic field. A Landau level scaling anomaly occurs when the charge is larger than the critical charge beta 0.6 and this critical charge is independent of the magnetic field. |
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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 |
|
Wos |
001199561900008 |
Publication Date |
2024-03-04 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
|
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| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:205508 |
Serial |
9137 |
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| Permanent link to this record |
| |
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| |
|
Author |
Yampolskii, S.V.; Peeters, F.M. |
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| |
Title |
Giant vortices in small mesoscopic disks : an approximate description |
Type |
A1 Journal article |
| |
Year |
2002 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
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| |
Volume |
369 |
Issue |
1/4 |
Pages |
347-350 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We present an approximate description of the giant vortex state in a thin mesoscopic superconducting disk within the phenomenological Ginzburg-Landau approach. Analytical asymptotic expressions for the energies of the states with fixed vorticity are obtained when a small magnetic flux is accumulated in the disk. The spectrum of the lowest Landau levels of such a disk is also discussed. (C) 2001 Elsevier Science B.V. All rights reserved. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000174200000063 |
Publication Date |
2002-07-25 |
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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 |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
1.404 |
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 1.404; 2002 IF: 0.912 |
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| |
Call Number |
UA @ lucian @ c:irua:94930 |
Serial |
1342 |
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| Permanent link to this record |
| |
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| |
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Author |
Baelus, B.J.; Yampolskii, S.V.; Peeters, F.M. |
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| |
Title |
Magnetic coupling between mesoscopic superconducting rings |
Type |
A1 Journal article |
| |
Year |
2002 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
|
| |
Volume |
369 |
Issue |
1/4 |
Pages |
366-369 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Using the nonlinear Ginzburg-Landau theory we investigated the dependence of the magnetic coupling between two concentric mesoscopic superconducting rings on their thickness. The size of this magnetic coupling increases with the thickness of the rings. (C) 2001 Elsevier Science B.V. All rights reserved. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000174200000067 |
Publication Date |
2002-07-25 |
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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 |
0921-4534; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.404 |
Times cited |
1 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 1.404; 2002 IF: 0.912 |
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| |
Call Number |
UA @ lucian @ c:irua:94931 |
Serial |
1865 |
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| Permanent link to this record |
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| |
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Author |
Novoselov, K.S.; Geim, A.K.; Dubonos, S.V.; Cornelissens, Y.G.; Peeters, F.M.; Maan, J.C. |
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| |
Title |
Quenching of the Hall effect in localised high magnetic field regions |
Type |
A1 Journal article |
| |
Year |
2002 |
Publication |
Physica. E: Low-dimensional systems and nanostructures |
Abbreviated Journal |
Physica E |
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| |
Volume |
12 |
Issue |
1/4 |
Pages |
244-247 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report the suppression of the Hall effect in a mesoscopic Hall cross with a strong magnetic field only in the centre and vanishingly small outside, The local magnetic field is produced by placing Dy pillar on top of a structure with a high-mobility two-dimensional electron gas. The effect is found to be due to a sharp increase of the number of back-scattered and quasi-localised electron orbits. The possibility of localising electrons inside the magnetic inhomogeneity region is discussed. (C) 2002 Elsevier Science B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000175206300061 |
Publication Date |
2002-10-15 |
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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 |
1386-9477; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.221 |
Times cited |
3 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 2.221; 2002 IF: 1.107 |
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| |
Call Number |
UA @ lucian @ c:irua:94939 |
Serial |
2804 |
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| Permanent link to this record |
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Author |
Sorée, B.; Magnus, W. |
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Title |
Quantized conductance without reservoirs : method of the nonequilibrium statistical operator |
Type |
A1 Journal article |
| |
Year |
2007 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
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| |
Volume |
6 |
Issue |
1/3 |
Pages |
255-258 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We introduce a generalized non-equilibrium statistical operator (NSO) to study a current-carrying system. The NSO is used to derive a set of quantum kinetic equations based on quantum mechanical balance equations. The quantum kinetic equations are solved self-consistently together with Poissons equation to solve a general transport problem. We show that these kinetic equations can be used to rederive the Landauer formula for the conductance of a quantum point contact, without any reference to reservoirs at different chemical potentials. Instead, energy dissipation is taken into account explicitly through the electron-phonon interaction. We find that both elastic and inelastic scattering are necessary to obtain the Landauer conductance. |
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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 |
S.l. |
Editor |
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Language |
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Wos |
000208473600062 |
Publication Date |
2007-01-17 |
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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 |
1569-8025;1572-8137; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
1.526 |
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 1.526; 2007 IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:89506 |
Serial |
2769 |
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| Permanent link to this record |
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Author |
Karapetrov, G.; Belkin, A.; Iavarone, M.; Fedor, J.; Novosad, V.; Milošević, M.V.; Peeters, F.M. |
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| |
Title |
Anisotropic superconductivity and vortex dynamics in magnetically coupled F/S and F/S/F hybrids |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
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| |
Volume |
24 |
Issue |
1/2 |
Pages |
905-910 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Magnetically coupled superconductorferromagnet hybrids offer advanced routes for nanoscale control of superconductivity. Magnetotransport characteristics and scanning tunneling microscopy images of vortex structures in superconductorferromagnet hybrids reveal rich superconducting phase diagrams. Focusing on a particular combination of a ferromagnet with a well-ordered periodic magnetic domain structure with alternating out-of-plane component of magnetization, and a small coherence length superconductor, we find directed nucleation of superconductivity above the domain wall boundaries. We show that near the superconductor-normal state phase boundary the superconductivity is localized in narrow mesoscopic channels. In order to explore the Abrikosov flux line ordering in F/S hybrids, we use a combination of scanning tunneling microscopy and GinzburgLandau simulations. The magnetic stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinninganti-pinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-1D arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. In F/S/F hybrids we demonstrate the evolution of the anisotropic conductivity in the superconductor that is magnetically coupled with two adjacent ferromagnetic layers. Stripe magnetic domain structures in both F-layers are aligned under each other, resulting in a directional superconducting order parameter in the superconducting layer. The conductance anisotropy strongly depends on the period of the magnetic domains and the strength of the local magnetization. The anisotropic conductivity of up to three orders of magnitude can be achieved with a spatial critical temperature modulation of 5% of T c. Induced anisotropic properties in the F/S and F/S/F hybrids have a potential for future application in switching and nonvolatile memory elements operating at low temperatures. |
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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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
000289855700150 |
Publication Date |
2010-10-01 |
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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 |
1557-1939;1557-1947; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.18 |
Times cited |
2 |
Open Access |
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| |
Notes |
; This work as well as the use of the Center for Nanoscale Materials and the Electron Microscopy Center at Argonne National Laboratory were supported by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. This work was also supported by the Ministry of Education, Agency for Structural Funds of the European Union, Research and Development Program, under agreement 262 401 200 19. M.V.M. and F. M. P. acknowledge support from the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, the JSPS/ESF-NES program, the ESF-AQDJJ network, and the Vlaanderen-USA bilateral program. ; |
Approved |
Most recent IF: 1.18; 2011 IF: 0.650 |
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| |
Call Number |
UA @ lucian @ c:irua:89930 |
Serial |
130 |
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| Permanent link to this record |
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| |
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Author |
Sels, D.; Brosens, F.; Magnus, W. |
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| |
Title |
Classical trajectories : a powerful tool for solving tunneling problems |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica: A : theoretical and statistical physics |
Abbreviated Journal |
Physica A |
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| |
Volume |
391 |
Issue |
1/2 |
Pages |
78-81 |
|
| |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
|
| |
Abstract |
In the realm of Ehrenfests theorem, classical trajectories obeying Newtons laws have been proven useful to construct explicit solutions to the time-dependent WignerLiouville equation. Whereas previous works have particularly focused on the initial distribution function as a vehicle found to carry the signatures of quantum statistics into the time-dependent solution, the present paper shows that the LagrangeCharpit method based on classical trajectories can be successfully invoked as well to tackle quantum mechanical features with no classical counterpart, such as tunneling. |
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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 |
Amsterdam |
Editor |
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| |
Language |
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Wos |
000297230700010 |
Publication Date |
2011-08-25 |
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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 |
0378-4371; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.243 |
Times cited |
7 |
Open Access |
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|
| |
Notes |
; ; |
Approved |
Most recent IF: 2.243; 2012 IF: 1.676 |
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| |
Call Number |
UA @ lucian @ c:irua:92359 |
Serial |
370 |
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| Permanent link to this record |
