Records |
Author |
Tso, H.C.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Coupled electron-hole transport: generalized random-phase approximation and density functional theory |
Type |
A1 Journal article |
Year |
1994 |
Publication |
Surface science : a journal devoted to the physics and chemistry of interfaces |
Abbreviated Journal |
Surf Sci |
Volume |
305 |
Issue |
|
Pages |
400-404 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
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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 |
A1994ND67400076 |
Publication Date |
2002-10-18 |
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 |
|
ISSN |
0039-6028; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.925 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
PHYSICS, APPLIED 47/145 Q2 # |
Call Number |
UA @ lucian @ c:irua:9380 |
Serial |
535 |
Permanent link to this record |
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Author |
Berger, J.; Milošević, M.V. |
Title |
Fluctuations in superconducting rings with two order parameters |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
21 |
Pages |
214515-214515,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Motivated by two-band superconductivity in, e.g., borides and pnictides, starting from the two-band Ginzburg-Landau energy functional, we discuss how the presence of two order parameters and the coupling between them influence a superconducting ring in the fluctuative regime. Our method is an extension of the von OppenRiedel formalism for rings; it is exact, but requires numerical implementation. We also study approximations for which analytic expressions can be obtained, and check their ranges of validity. We provide estimates for the temperature ranges where fluctuations are important, calculate the persistent current in MgB2 rings as a function of temperature and enclosed flux, and point out its additional dependence on the cross-section area of the wire from which the ring is made. We find temperature regions in which fluctuations enhance the persistent currents and regions where they inhibit the persistent current. The presence of two order parameters that can fluctuate independently always leads to larger averages of the order parameters at Tc, but yields larger persistent current only for appropriate parameters. In cases of very different material parameters for the two coupled condensates, the persistent current is inhibited. |
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 |
000297932500004 |
Publication Date |
2011-12-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
Notes |
; This research was supported by the Israel Science Foundation, Grant No. 249/10, the Flemish Science Foundation (FWO-Vl), and the ESF network INSTANS. We are grateful to Andrei Varlamov and Felix von Oppen for their answers to our enquiries. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:93957 |
Serial |
1226 |
Permanent link to this record |
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Author |
Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
Title |
Energy levels of triangular and hexagonal graphene quantum dots : a comparative study between the tight-binding and Dirac equation approach |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
24 |
Pages |
245403-245403,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Dirac equation is solved for triangular and hexagonal graphene quantum dots for different boundary conditions in the presence of a perpendicular magnetic field. We analyze the influence of the dot size and its geometry on their energy spectrum. A comparison between the results obtained for graphene dots with zigzag and armchair edges, as well as for infinite-mass boundary condition, is presented and our results show that the type of graphene dot edge and the choice of the appropriate boundary conditions have a very important influence on the energy spectrum. The single-particle energy levels are calculated as a function of an external perpendicular magnetic field that lifts degeneracies. Comparing the energy spectra obtained from the tight-binding approximation to those obtained from the continuum Dirac equation approach, we verify that the behavior of the energies as a function of the dot size or the applied magnetic field are qualitatively similar, but in some cases quantitative differences can exist. |
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 |
000297767800008 |
Publication Date |
2011-12-07 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
145 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE (project CONGRAN), the Bilateral program between Flanders and Brazil, CAPES and the Brazilian Council for Research (CNPq). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:93961 |
Serial |
1040 |
Permanent link to this record |
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Author |
Covaci, L.; Peeters, F.M. |
Title |
Superconducting proximity effect in graphene under inhomogeneous strain |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
24 |
Pages |
241401-241401,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The interplay between quantum Hall states and Cooper pairs is usually hindered by the suppression of the superconducting state due to the strong magnetic fields needed to observe the quantum Hall effect. From this point of view, graphene is special since it allows the creation of strong pseudomagnetic fields due to strain. We show that in a Josephson junction made of strained graphene, Cooper pairs will diffuse into the strained region. The pair correlation function will be sublattice polarized due to the polarization of the local density of states in the zero pseudo-Landau level. We uncover two regimes: (1) one in which the cyclotron radius is larger than the junction length, in which case the supercurrent will be enhanced, and (2) the long junction regime where the supercurrent is strongly suppressed because the junction becomes an insulator. In the latter case quantized Hall states form and Andreev scattering at the normal/superconducting interface will induce edge states. Our numerical calculation has become possible due to an extension of the Chebyshev-Bogoliubovde Gennes method to computations on video cards (GPUs). |
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 |
000297766600003 |
Publication Date |
2011-12-06 |
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 |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
27 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Euro GRAPHENE project CONGRAN. Discussions with Andrey Chaves are gratefully acknowledged. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:93962 |
Serial |
3364 |
Permanent link to this record |
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Author |
Stankovski, M.; Antonius, G.; Waroquiers, D.; Miglio, A.; Dixit, H.; Sankaran, K.; Giantomassi, M.; Gonze, X.; Côté, M.; Rignanese, G.-M. |
Title |
G0W0 band gap of ZnO : effects of plasmon-pole models |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
24 |
Pages |
241201-241201,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Carefully converged calculations are performed for the band gap of ZnO within many-body perturbation theory (G0W0 approximation). The results obtained using four different well-established plasmon-pole models are compared with those of explicit calculations without such models (the contour-deformation approach). This comparison shows that, surprisingly, plasmon-pole models depending on the f-sum rule gives less precise results. In particular, it confirms that the band gap of ZnO is underestimated in the G0W0 approach as compared to experiment, contrary to the recent claim of Shih et al. [ Phys. Rev. Lett. 105 146401 (2010)]. |
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 |
000297766600001 |
Publication Date |
2011-12-06 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
81 |
Open Access |
|
Notes |
; The authors would like to thank P. Zhang, S. Louie, J. Deslippe, P. Rinke, H. Jiang, C. Friedrich, and F. Bruneval for many helpful discussions. We are also very grateful to Y. Pouillon, A. Jacques, and J.-M. Beuken for their technical aid and expertise. M.C. and G.A. would like to acknowledge the support of NSERC and FQRNT. This work was supported by the Interuniversity Attraction Poles program (P6/42)-Belgian State-Belgian Science Policy, the Flemish Science Foundation (FWO-Vl) ISIMADE project, the EU's 7th Framework programme through the ETSF I3 e-Infrastructure project (Grant Agreement No. 211956), the Communaute francaise de Belgique, through the Action de Recherche Concertee 07/ 12-003 “Nanosystemes hybrides metal-organiques”, and the FNRS through FRFC Project No. 2.4.589.09.F. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:93963 |
Serial |
3533 |
Permanent link to this record |
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Author |
Peeters, F.M.; Wu, X.G.; Devreese, J.T. |
Title |
Magneto-phonon resonances in the resistance and the optical absorption spectrum of heterostructures |
Type |
A1 Journal article |
Year |
1991 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
Volume |
T39 |
Issue |
|
Pages |
302-307 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
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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 |
Stockholm |
Editor |
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Language |
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Wos |
A1991GV57300047 |
Publication Date |
2007-01-26 |
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 |
0031-8949;1402-4896; |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
1.126 |
Times cited |
|
Open Access |
|
Notes |
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Approved |
no |
Call Number |
UA @ lucian @ c:irua:940 |
Serial |
1907 |
Permanent link to this record |
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Author |
Sels, D.; Brosens, F.; Magnus, W. |
Title |
On the path integral representation of the Wigner function and the BarkerMurray ansatz |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physics letters : A |
Abbreviated Journal |
Phys Lett A |
Volume |
376 |
Issue |
6/7 |
Pages |
809-812 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
Abstract |
The propagator of the Wigner function is constructed from the WignerLiouville equation as a phase space path integral over a new effective Lagrangian. In contrast to a paper by Barker and Murray (1983) [1], we show that the path integral can in general not be written as a linear superposition of classical phase space trajectories over a family of non-local forces. Instead, we adopt a saddle point expansion to show that the semiclassical Wigner function is a linear superposition of classical solutions for a different set of non-local time dependent forces. As shown by a simple example the specific form of the path integral makes the formulation ideal for Monte Carlo simulation. |
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 |
000301167300005 |
Publication Date |
2012-01-17 |
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 |
0375-9601; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.772 |
Times cited |
7 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.772; 2012 IF: 1.766 |
Call Number |
UA @ lucian @ c:irua:94006 |
Serial |
2445 |
Permanent link to this record |
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Author |
Grujić, M.; Zarenia, M.; Chaves, A.; Tadić, M.; Farias, G.A.; Peeters, F.M. |
Title |
Electronic and optical properties of a circular graphene quantum dot in a magnetic field : influence of the boundary conditions |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
20 |
Pages |
205441-205441,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
An analytical approach, using the Dirac-Weyl equation, is implemented to obtain the energy spectrum and optical absorption of a circular graphene quantum dot in the presence of an external magnetic field. Results are obtained for the infinite-massand zigzag boundary conditions. We found that the energy spectrum of a dot with the zigzag boundary condition exhibits a zero-energy band regardless of the value of the magnetic field, while for the infinite-mass boundary condition, the zero-energy states appear only for high magnetic fields. The analytical results are compared to those obtained from the tight-binding model: (i) we show the validity range of the continuum model and (ii) we find that the continuum model with the infinite-mass boundary condition describes rather well its tight-binding analog, which can be partially attributed to the blurring of the mixed edges by the staggered potential. |
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 |
000297295400011 |
Publication Date |
2011-11-21 |
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 |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
78 |
Open Access |
|
Notes |
; This work was supported by the EuroGraphene programme of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP), the bilateral projects between Flanders and Brazil, the Flemish Science Foundation (FWO-Vl), and the Brazilian Research Council (CNPq). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94025 |
Serial |
997 |
Permanent link to this record |
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Author |
Sena, S.H.R.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. |
Title |
Landau levels in asymmetric graphene trilayer |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
20 |
Pages |
205448-205448,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic spectrum of three coupled graphene layers (graphene trilayers) is investigated in the presence of an external magnetic field. We obtain analytical expressions for the Landau level spectrum for both the ABA and ABC type of stacking, which exhibit very different dependence on the magnetic field. We show that layer asymmetry and an external gate voltage can strongly influence the properties of the system. |
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 |
000297295400018 |
Publication Date |
2011-11-21 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
30 |
Open Access |
|
Notes |
; This work was supported by the Brazilian Council for Research (CNPq), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral projects between Flanders and Brazil and the CNPq and FWO-Vl. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94026 |
Serial |
1773 |
Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B. |
Title |
Theory of phonon dispersions and piezoelectricity in multilayers of hexagonal boron-nitride |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
248 |
Issue |
11 |
Pages |
2720-2723 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Taking into account covalent, Coulomb and van der Waals interactions, we construct the dynamical matrix and calculate the phonon dispersion relations for multilayer crystals of hexagonal boron-nitride. Coulomb interactions account for a strong overbending of optical phonons. Applying and extending Born's long-wave theory to the case of multilayer crystals, we calculate the piezoelectric stress constant equation image as a function of the number of layers equation image. In agreement with group theory, we find that equation image for equation image even; for an uneven number equation image of layers we obtain equation image, i.e. the piezoelectric constant decreases as equation image. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000297517100069 |
Publication Date |
2011-10-18 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
13 |
Open Access |
|
Notes |
; Discussions with G. Heger, B. Partoens and F. M. Peeters are gratefully acknowledged. This work has been supported by the Flemish Science Foundation (FWO-Vl) and the Bijzonder Onderzoeksfonds, Universiteit Antwerpen (BOF-UA). ; |
Approved |
Most recent IF: 1.674; 2011 IF: 1.316 |
Call Number |
UA @ lucian @ c:irua:94034 |
Serial |
3618 |
Permanent link to this record |
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Author |
Tkachenko, D.V.; Sheridan, T.E.; Misko, V.R. |
Title |
Dispersion relations for circular single and double dusty plasma chains |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physics of plasmas |
Abbreviated Journal |
Phys Plasmas |
Volume |
18 |
Issue |
10 |
Pages |
103709,1-103709,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We derive dispersion relations for a system of identical particles confined in a two-dimensional annular harmonic well and which interact through a Yukawa potential, e.g., a dusty plasma ring. When the particles are in a single chain (i.e., a one-dimensional ring), we find a longitudinal acoustic mode and a transverse optical mode which show approximate agreement with the dispersion relation for a straight configuration for large radii of the ring. When the radius decreases, the dispersion relations modify: there appears an anticrossing of the modes near the crossing point resulting in a frequency gap between the lower and upper branches of the modified dispersion relations. For the double chain (i.e., a two-dimensional zigzag configuration), the dispersion relation has four branches: longitudinal acoustic and optical and transverse acoustic and optical. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Woodbury, N.Y. |
Editor |
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Language |
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Wos |
000296529600090 |
Publication Date |
2011-10-21 |
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 |
|
ISSN |
1070-664X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.115 |
Times cited |
7 |
Open Access |
|
Notes |
; We acknowledge fruitful discussions with F.M. Peeters, A. Matulis, and W.P. Ferreira. This work was supported by the “Odysseus” program of the Flemish Government and FWO-Vl. ; |
Approved |
Most recent IF: 2.115; 2011 IF: 2.147 |
Call Number |
UA @ lucian @ c:irua:94052 |
Serial |
738 |
Permanent link to this record |
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Author |
Nowak, M.P.; Szafran, B.; Peeters, F.M. |
Title |
Fano resonances and electron spin transport through a two-dimensional spin-orbit-coupled quantum ring |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
23 |
Pages |
235319-235319,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electron transport through a spin-orbit-coupled quantum ring is investigated within linear response theory. We show that the finite width of the ring results in the appearance of Fano resonances in the conductance. This turns out to be a consequence of the spin-orbit interaction that leads to a breaking of the parity of the states localized in the ring. The resonances appear when the system is close to maxima of Aharonov-Casher conductance oscillations where spin transfer is heavily modified. When the spin-orbit coupling strength is detuned from the Aharonov-Casher maxima the resonances are broadened resulting in a dependence of the spin transport on the electron Fermi energy in contrast to predictions from one-dimensional models. |
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 |
000298605700002 |
Publication Date |
2011-12-29 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
19 |
Open Access |
|
Notes |
; This work was supported by the “Krakow Interdisciplinary PhD Project in Nanoscience and Advanced Nanostructures” operated within the Foundation for Polish Science MPD Programme cofinanced by the EU European Regional Development Fund, Project No. N N202103938 supported by the Ministry of Science and Higher Education (MNiSW) for 2010-2013, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). This research was supported in part by PL-Grid Infrastructure. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94292 |
Serial |
1171 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M.; Axt, V.M. |
Title |
Parity-fluctuation induced enlargement of the ratio \DeltaE/kBTc in metallic grains |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
21 |
Pages |
214518-214518,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate how the interplay of quantum confinement and particle number-parity fluctuations affects superconducting correlations in ultra-small metallic grains. Using the number-parity projected BCS formalism we calculate the critical temperature and the excitation gap as a function of the grain size for grains with even and odd number of confined carriers. We show that the experimentally observed anomalous increase of the coupling ratio ΔE/kBTc with decreasing superconducting grain size can be attributed to an enhancement of the number-parity fluctuations in ultra-small grains. |
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 |
000298114100003 |
Publication Date |
2011-12-16 |
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 |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
Notes |
; This work was supported by the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flamish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). M. D. C. thanks A. S. Mel'nikov and N. B. Kopnin for fruitful discussions. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94373 |
Serial |
2555 |
Permanent link to this record |
|
|
|
Author |
Masir, M.R.; Matulis, A.; Peeters, F.M. |
Title |
Scattering of Dirac electrons by circular mass barriers : valley filter and resonant scattering |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
24 |
Pages |
245413-245413,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The scattering of two-dimensional (2D) massless Dirac electrons is investigated in the presence of a random array of circular mass barriers. The inverse momentum relaxation time and the Hall factor are calculated and used to obtain parallel and perpendicular resistivity components within linear transport theory. We found a nonzero perpendicular resistivity component which has opposite sign for electrons in the different K and K′ valleys. This property can be used for valley filter purposes. The total cross section for scattering on penetrable barriers exhibits resonances due to the presence of quasibound states in the barriers that show up as sharp gaps in the cross section while for Schrödinger electrons they appear as peaks. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000297934500008 |
Publication Date |
2011-12-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
32 |
Open Access |
|
Notes |
; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94383 |
Serial |
2951 |
Permanent link to this record |
|
|
|
Author |
Launois, P.; Chorro, M.; Verberck, B.; Albouy, P.-A.; Rouzière, S.; Colson, D.; Forget, A.; Noé, L.; Kataura, H.; Monthioux, M.; Cambedouzou, J. |
Title |
Transformation of C70 peapods into double walled carbon nanotubes |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
48 |
Issue |
1 |
Pages |
89-98 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
X-ray diffraction studies comparing the transformation of C(60) and C(70) peapods into double walled carbon nanotubes are presented. The structures of the as-formed DWCNTs are strikingly similar, showing that they are not dependent on the nature of the fullerene precursor. High temperature X-ray diffraction measurements of C(70) peapods below the coalescence temperature show that confined C(70) molecules in large tubes undergo an orientational. transition to free rotations. Fast re-orientations of C(70) molecules allow cyclo-addition between adjacent fullerenes to form, in good agreement with the mechanism of coalescence proposed in the literature for C(60) molecules. (C) 2009 Elsevier Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000272018800012 |
Publication Date |
2009-08-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
27 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 6.337; 2010 IF: 4.896 |
Call Number |
UA @ lucian @ c:irua:94389 |
Serial |
3696 |
Permanent link to this record |
|
|
|
Author |
Langerak, C.J.G.M.; Singleton, J.; Perenboom, J.A.A.; Devreese, J.T.; Barnes, D.J.; Nicholas, R.J.; Huant, S.; Harris, J.J.; Foxon, C.T.; Etienne, B.; Peeters, F.M. |
Title |
Far-infrared magneto-optical studies of the polaron effect in low dimensional GaAs-(Ga,Al)As structures |
Type |
A1 Journal article |
Year |
1991 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
Volume |
T39 |
Issue |
|
Pages |
308-313 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Stockholm |
Editor |
|
Language |
|
Wos |
A1991GV57300048 |
Publication Date |
2007-01-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.126 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:944 |
Serial |
1173 |
Permanent link to this record |
|
|
|
Author |
Milošević, M.V.; Kanda, A.; Hatsumi, S.; Peeters, F.M.; Ootuka, Y. |
Title |
Local current injection into mesoscopic superconductors for the manipulation of quantum states |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
103 |
Issue |
21 |
Pages |
217003-217003,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We perform strategic current injection in a small mesoscopic superconductor and control the (non)equilibrium quantum states in an applied homogeneous magnetic field. In doing so, we realize a current-driven splitting of multiquanta vortices, current-induced transitions between states with different angular momenta, and current-controlled switching between otherwise degenerate quantum states. These fundamental phenomena form the basis for the electronic and logic applications discussed, and are confirmed in both theoretical simulations and multiple-small-tunnel-junction transport measurements. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000272054300044 |
Publication Date |
2009-12-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
48 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2009 IF: 7.328 |
Call Number |
UA @ lucian @ c:irua:94498 |
Serial |
1826 |
Permanent link to this record |
|
|
|
Author |
Kálmán, O.; Földi, P.; Benedict, M.G.; Peeters, F.M. |
Title |
Magnetoconductance of rectangular arrays of quantum rings |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
12 |
Pages |
125306-125306,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electron transport through multiterminal rectangular arrays of quantum rings is studied in the presence of Rashba-type spin-orbit interaction (SOI) and of a perpendicular magnetic field. Using the analytic expressions for the transmission and reflection coefficients for single rings we obtain the conductance through such arrays as a function of the SOI strength, of the magnetic flux, and of the wave vector k of the incident electron. Due to destructive or constructive spin interferences caused by the SOI, the array can be totally opaque for certain ranges of k, while there are parameter values where it is completely transparent. Spin resolved transmission probabilities show nontrivial spin transformations at the outputs of the arrays. When pointlike random scattering centers are placed between the rings, the Aharonov-Bohm peaks split, and an oscillatory behavior of the conductance emerges as a function of the SOI strength. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000259691500047 |
Publication Date |
2008-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
31 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:94598 |
Serial |
1913 |
Permanent link to this record |
|
|
|
Author |
Ludu, A. |
Title |
Fiber bundle description of flow and nonlinear hydrodynamics on circles |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of nonlinear mathematical physics |
Abbreviated Journal |
J Nonlinear Math Phy |
Volume |
15 |
Issue |
|
Pages |
157-170 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We introduce a differential geometry description of the path lines, stream lines and particles contours in hydrodynamics. We present a generalized form of a Korteweg-de Vries type of equation for the exterior of a circle. Nonlinearities from the boundary conditions, surface tension and the Euler equations are taken into account, but the flow is considered inviscid and irrotational. For the circular case we describe the traveling waves shapes, solitons and the particles trajectories. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000263517200012 |
Publication Date |
2008-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1402-9251;1776-0852; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.986 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.986; 2008 IF: 0.760 |
Call Number |
UA @ lucian @ c:irua:94603 |
Serial |
1189 |
Permanent link to this record |
|
|
|
Author |
Misko, V.R.; Savel'ev, S.; Rakhmanov, A.L.; Nori, F. |
Title |
Nonuniform self-organized dynamical states in superconductors with periodic pinning |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
96 |
Issue |
12 |
Pages |
127004-127004,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We consider magnetic flux moving in superconductors with periodic pinning arrays. We show that sample heating by moving vortices produces negative differential resistivity (NDR) of both N and S type (i.e., N- and S-shaped) in the voltage-current characteristic (VI curve). The uniform flux flow state is unstable in the NDR region of the VI curve. Domain structures appear during the NDR part of the VI curve of an N type, while a filamentary instability is observed for the NDR of an S type. The simultaneous existence of the NDR of both types gives rise to the appearance of striking self-organized (both stationary and nonstationary) two-dimensional dynamical structures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000236467000064 |
Publication Date |
2006-03-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
31 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2006 IF: 7.072 |
Call Number |
UA @ lucian @ c:irua:94690 |
Serial |
2364 |
Permanent link to this record |
|
|
|
Author |
Benedict, M.G.; Földi, P.; Peeters, F.M. |
Title |
Terahertz radiation from crystals of nanomagnets |
Type |
P1 Proceeding |
Year |
2006 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
Volume |
36 |
Issue |
|
Pages |
12-17 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
Certain crystals, consisting of molecules with unusually large spin, exhibit macroscopically observable signatures of quantum tunneling, when a slowly varying external magnetic field is applied parallel to the easy axis of the crystal. Recently it has been observed that jumps in the magnetization are sometimes accompanied by the emission of infrared radiation. We discuss the connection of the tunneling with the electromagnetic transition, and we address the questions: to what extent can the radiation be considered as a collective, superradiant emission, and what is the role played by the cavity in the experiments? Our conclusion is that among the reported experimental coditions the radiation is not superradidance, but rather a maserlike effect. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000239847500003 |
Publication Date |
2006-05-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1742-6588;1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:94695 |
Serial |
3508 |
Permanent link to this record |
|
|
|
Author |
Michel, K.H.; Verberck, B.; Nikolaev, A.V. |
Title |
Anisotropic packing and one-dimensional fluctuations of C60 molecules in carbon nanotubes |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
95 |
Issue |
18 |
Pages |
185506-185506,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The confinement of a C-60 molecule encapsulated in a cylindrical nanotube depends on the tube radius. In small tubes with radius R-T less than or similar to 7 A, a fivefold axis of the molecule coincides with the tube axis. The interaction between C-60 molecules in the nanotube is then described by a O-2-rotor model on a 1D liquid chain with coupling between orientational and displacive correlations. This coupling leads to chain contraction. The structure factor of the 1D liquid is derived. In tubes with a larger radius the molecular centers of mass are displaced off the tube axis. The distinction of two groups of peapods with on- and off-axis molecules suggests an explanation of the apparent splitting of A(g) modes of C-60 in nanotubes measured by resonant Raman scattering. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000232887400041 |
Publication Date |
2005-10-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
40 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2005 IF: 7.489 |
Call Number |
UA @ lucian @ c:irua:94717 |
Serial |
127 |
Permanent link to this record |
|
|
|
Author |
Degani, M.H.; Farias, G.A.; Peeters, F.M. |
Title |
Bound states and lifetime of an electron on a bulk helium surface |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
72 |
Issue |
12 |
Pages |
125408-125408,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We propose an effective potential for an excess electron near the helium liquid-vapor interface that takes into account the diffuseness of the liquid-vapor interface and the classical image potential. The splitting of the first two excited states of the excess electron bound to the helium liquid-vapor interface as a function of an external constant electric field applied perpendicular to the interface is in excellent agreement with recent experiments. The effect of a parallel magnetic field on the energy levels are calculated. Single-electron tunneling of the electron out of its surface state is studied as a function of the electric field applied to the system. We found that the tunneling time has a linear dependence on the electric field. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000232229400125 |
Publication Date |
2005-09-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2005 IF: 3.185 |
Call Number |
UA @ lucian @ c:irua:94719 |
Serial |
251 |
Permanent link to this record |
|
|
|
Author |
Kanda, A.; Baelus, B.J.; Peeters, F.M.; Kadowaki, K.; Ootuka, Y. |
Title |
Observation of paramagnetic supercurrent in mesoscopic superconducting rings and disks using multiple-small-tunnel-junction method |
Type |
P1 Proceeding |
Year |
2005 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
204-209 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
Responses of mesoscopic superconducting rings and disks to perpendicular magnetic fields are studied by using the multiple-small-tunnel-junction method, in which transport properties of several small tunnel junctions attached to the sample are measured simultaneously. This allows us for a direct experimental observation of the paramagnetic supercurrent, which is closely related to the paramagnetic Meissner effect. The results are compared with numerical results based on the nonlinear Ginzburg-Landau theory. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
World Scientific |
Place of Publication |
Singapore |
Editor |
|
Language |
|
Wos |
000234363700032 |
Publication Date |
2007-11-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:94758 |
Serial |
2419 |
Permanent link to this record |
|
|
|
Author |
Mattauch, S.; Heger, G.; Michel, K.H. |
Title |
High resolution neutron and X-ray diffraction studies as a function of temperature and electric field of the ferroelectric phase transition of RDP |
Type |
A1 Journal article |
Year |
2004 |
Publication |
Crystal research and technology |
Abbreviated Journal |
Cryst Res Technol |
Volume |
39 |
Issue |
12 |
Pages |
1027-1054 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Neutron and high resolution X-ray diffraction investigations on perfect single crystals of RbH2PO4 (RDP), a hydrogen bonded ferroelectric of KDP type are reported. The results of crystal structure analysis from diffraction data, below and above the paraelectric – ferroelectric phase transition, support a disorder – order character Of [PO4H2](-)-groups. The tetragonal symmetry of the paraelectric phase with the double well potential of the hydrogen atoms obtained by diffraction, results simply from a time-space average of orthorhombic symmetry. According to the group – subgroup relation between the tetragonal space group 142d and the orthorhombic Fdd2 a short range order of ferroelectric clusters in the tetragonal phase is observed. With decreasing temperature the ferroelectric clusters increase and the long range interaction between their local polarisation vectors leads to the formation of lamellar ferroelectric domains with alternating polarisation directions at T-C = 147 K. From the high resolution X-ray data it is concluded that below T-C the ferroelastic strain in the (a,b)-plane leads to micro-angle grain boundaries at the domain walls. The tilt angle is enhanced by an applied electric field parallel to the ferroelectric axis. The resulting dislocations at the domain walls persist in the paraelectric phase leading to a memory effect for the arrangement of twin lamellae. With increased electric field the phase transition temperature T-C is decreased. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000225681100001 |
Publication Date |
2004-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0232-1300;1521-4079; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1; 2004 IF: 0.770 |
Call Number |
UA @ lucian @ c:irua:94785 |
Serial |
1459 |
Permanent link to this record |
|
|
|
Author |
Vasilopoulos, P.; Molnar, B.; Peeters, F.M. |
Title |
Magnetoconductance through a chain of rings in the presence of spin-orbit interaction |
Type |
A1 Journal article |
Year |
2004 |
Publication |
International journal of modern physics: B: condensed matter physics, statistical physics, applied physics |
Abbreviated Journal |
Int J Mod Phys B |
Volume |
18 |
Issue |
27-29 |
Pages |
3661-3664 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Ballistic electron transport through a finite chain of quantum circular rings is studied in the presence of the Rashba coupling, of strength a, and of a perpendicular magnetic field B. The transmission and reflection coefficients for a single ring, obtained analytically, help obtain the conductance through a chain of rings as a function of the strength a, the field B, and of the wave vector k of the incident electron. Due to destructive spin interferences caused by the Rashba coupling the chain can be totally opaque for certain ranges of k the width of which depends on values of a and B. Outside these ranges the conductance oscillates with high values between e(2)/h and 2e(2)/h. The effect of a periodic modulation of a or B on the conductance gaps is investigated. A periodic, square-wave conductance pattern, pertinent to the development of the spin transistor, results within wide stripes in the parameter space spanned by k, a, and B. Finite temperatures smoothen the square-wave profile of the conductance but do not alter its periodic character. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Singapore |
Editor |
|
Language |
|
Wos |
000227140200042 |
Publication Date |
2005-04-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0217-9792;1793-6578; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.736 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.736; 2004 IF: 0.361 |
Call Number |
UA @ lucian @ c:irua:94787 |
Serial |
1914 |
Permanent link to this record |
|
|
|
Author |
Molnar, B.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Spin-dependent transmission through a chain of rings : influence of a periodically modulated spin-orbit interaction strength or ring radius |
Type |
A1 Journal article |
Year |
2004 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
85 |
Issue |
4 |
Pages |
612-614 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study ballistic electron transport through a finite chain of quantum circular rings in the presence of spin-orbit interaction of strength alpha. For a single ring, the transmission and reflection coefficients are obtained analytically and from them the conductance for a chain of rings as a function of alpha and of the wave vector k of the incident electron. We show that due to destructive spin interferences, the chain can be totally opaque for certain ranges of k, the width of which depends on the value of alpha. A periodic modulation of the strength alpha or of the ring radius widens the gaps considerably and produces a nearly binary conductance output. (C) 2004 American Institute of Physics. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000222855400034 |
Publication Date |
2004-07-23 |
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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
26 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2004 IF: 4.308 |
Call Number |
UA @ lucian @ c:irua:94799 |
Serial |
3085 |
Permanent link to this record |
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Author |
Nikolaev, A.V.; Michel, K.H. |
Title |
Symmetry lowering at the structural phase transitions in NpO2 and UO2 |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
68 |
Issue |
5 |
Pages |
054112-054112,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The structural phase transitions with electric-quadrupole long-range order in NpO2 (Fm (3) over barm-->Pn (3) over barm) and UO2 (Fm (3) over barm-->Pa (3) over bar) are analyzed from a group theoretical point of view. In both cases, the symmetry lowering involves three quadrupolar components belonging to the irreducible representation T-2g (Gamma(5)) of O-h and condensing in a triple-q structure at the X point of the Brillouin zone. The Pa (3) over bar structure is close to Pn (3) over barm, but allows for oxygen displacements. The Pa (3) over bar ordering leads to an effective electrostatic attraction between electronic quadrupoles while the Pn (3) over barm ordering results in a repulsion between them. It is concluded that the Pn (3) over barm structure can be stabilized only through some additional process such as strengthening of the chemical bonding between Np and O. We also derive the relevant structure-factor amplitudes for Pn (3) over barm and Pa (3) over bar, and the effect of domains on resonant x-ray scattering experiments. |
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 |
000185240100038 |
Publication Date |
2003-08-29 |
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 |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2003 IF: NA |
Call Number |
UA @ lucian @ c:irua:94847 |
Serial |
3405 |
Permanent link to this record |
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Author |
Betouras, J.J.; Ivanov, V.A.; Peeters, F.M. |
Title |
Ginzburg-Landau theory and effects of pressure on a two-band superconductor : application to MgB2 |
Type |
A1 Journal article |
Year |
2003 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
31 |
Issue |
3 |
Pages |
349-354 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a model of pressure effects of a two-band superconductor based on a Ginzburg-Landau free energy with two order parameters. The parameters of the theory are pressure as well as temperature dependent. New pressure effects emerge as a result of the competition between the two bands. The theory then is applied to MgB2. We identify two possible scenaria regarding the fate of the two Q subbands under pressure, depending on whether or not both subbands are above the Fermi energy at ambient pressure. The splitting of the two subbands is probably caused by the E-2g, distortion. If only one subband is above the Fermi energy at ambient pressure (scenario I), application of pressure diminishes the splitting and it is possible that the lower subband participates in the superconductivity. The corresponding crossover pressure and Gruneisen parameter are estimated. In the second scenario both bands start above the Fermi energy and they move below it, either by pressure or via the substitution of Mg by Al. In both scenaria, the possibility of electronical topological transition is emphasized. Experimental signatures of both scenaria are presented and existing experiments are discussed in the light of the different physical pictures. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000181614300008 |
Publication Date |
2004-03-20 |
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 |
1434-6028;1434-6036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.461; 2003 IF: 1.457 |
Call Number |
UA @ lucian @ c:irua:94859 |
Serial |
1343 |
Permanent link to this record |
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Author |
Vodolazov, D.I.; Peeters, F.M. |
Title |
Dynamic transitions between metastable states in a superconducting ring |
Type |
A1 Journal article |
Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
66 |
Issue |
5 |
Pages |
054537-054537,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Applying the time-dependent Ginzburg-Landau equations, transitions between metastable states of a superconducting ring are investigated in the presence of an external magnetic field. It is shown that if the ring exhibits several metastable states at a particular magnetic field, the transition from one metastable state to another one is governed by both the relaxation time of the absolute value of the order parameter tau(\psi\) and the relaxation time of the phase of the order parameter tau(phi). We found that the larger the ratio tau(\psi\)/tau(phi), the closer the final state will be to the absolute minimum of the free energy, i.e., the thermodynamic equilibrium. The transition to the final state occurs through a subsequent set of single phase slips at a particular point along the ring. |
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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 |
000177873000143 |
Publication Date |
2002-08-30 |
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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
34 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2002 IF: NA |
Call Number |
UA @ lucian @ c:irua:94917 |
Serial |
768 |
Permanent link to this record |