Records |
Author |
Shanenko, A.A.; Croitoru, M.D.; Vagov, A.; Peeters, F.M. |
Title |
Superconducting nanowires : new type of BCS-BEC crossover driven by quantum-size effects |
Type |
P1 Proceeding |
Year |
2011 |
Publication |
|
Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
119-127 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
We show that a superconducting quantum nanowire undergoes a new type of BCS-BEC crossover each time when an electron subband approaches the Fermi surface. In this case the longitudinal Cooper-pair size drops by two-three orders of magnitude down to a few nanometers. This unconventional BCS-BEC crossover is driven by quantum-size effects rather than by tuning the fermion-fermion interaction. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Springer |
Place of Publication |
Dordrecht |
Editor |
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Language |
|
Wos |
000289872900009 |
Publication Date |
2010-12-11 |
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 |
1874-6500;1874-6535; |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the ESF-network: INSTANS. M.D.C. acknowledges support from the Alexander von Humboldt Foundation. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:89946 |
Serial |
3359 |
Permanent link to this record |
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|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
Title |
Superconducting nanowires: quantum-confinement effect on the critical magnetic field and supercurrent |
Type |
P1 Proceeding |
Year |
2010 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
327-338 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
We study the effect, of electron confinement on the superconducting-to-normal phase transition driven by a magnetic field and/or on the current-carrying state of the superconducting condensate in nanowires. Our investigation is based on a self-consistent. numerical solution of the Bogoliubov-de Gennes equations. We show that, in a parallel magnetic field and/or in the presence of supercurrent the transition from superconducting to normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magnetic held exhibits quantum-size oscillations with pronounced resonant enhancements. |
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 |
000278418300025 |
Publication Date |
2010-04-08 |
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 |
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ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), Interuni-versity Attraction Poles Programme -Belgian State -Belgian Science Policy (IAP) and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:83294 |
Serial |
3361 |
Permanent link to this record |
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|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Superconductivity in the quantum-size regime |
Type |
P1 Proceeding |
Year |
2008 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
79-103 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
Recent technological advances resulted in high-quality superconducting metallic nanofilms and nanowires. The physical properties of such nanostructures are governed by the size-quantization of the transverse electron spectrum. This has a substantial impact on the basic superconducting characteristics, e.g., the order parameter, the critical temperature and the critical magnetic field. In the present paper we give an overview of our theoretical results on this subject. Based on a numerical self-consistent solution of the Bogoliubov-de Gennes equations, we investigate how the superconducting properties are modified in the quantum-size regime. |
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 |
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Publication Date |
0000-00-00 |
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 |
978-1-4020-9144-5 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:75944 |
Serial |
3374 |
Permanent link to this record |
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|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
Title |
Tuning the superconducting properties of nanomaterials |
Type |
H1 Book chapter |
Year |
2009 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
1-14 |
Keywords |
H1 Book chapter; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
Electron continement and its effect on the superconducting-to-normal phase transition driven by a magentic field and/or a current is studied in nanowires. Our investigation is based on a self-consistent numerical solution of the Bogoliubov-de Gennes equations. We find that in a parallel magneitc field and/or in the presence of a supercurrent the transition from the superconducting to the normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magentic field exhibits quantum-size oscillations with pronounced resonant enhancements as a function of the wire radius. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Springer |
Place of Publication |
Dordrecht |
Editor |
|
Language |
|
Wos |
000274282900001 |
Publication Date |
2009-07-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1874-6500; |
ISBN |
978-90-481-3118-1 |
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:99226 |
Serial |
3761 |
Permanent link to this record |
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|
|
Author |
Shanenko, A.A.; Orlova, N.V.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
Title |
Nanofilms as quantum-engineered multiband superconductors : the Ginzburg-Landau theory |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
102 |
Issue |
2 |
Pages |
27003-27006 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Recently fabricated single-crystalline atomically flat metallic nanofilms are in fact quantum-engineered multiband superconductors. Here the multiband structure is dictated by the nanofilm thickness through the size quantization of the electron motion perpendicular to the nanofilm. This opens the unique possibility to explore superconductivity in well-controlled multi-band systems. However, a serious obstacle is the absence of a convenient and manageable theoretical tool to access new physical phenomena in such quasi-two-dimensional systems, including interplay of quantum confinement and fluctuations. Here we cover this gap and construct the appropriate multiband Ginzburg-Landau functional for nano-thin superconductors. Copyright (C) EPLA, 2013 |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Paris |
Editor |
|
Language |
|
Wos |
000319617700019 |
Publication Date |
2013-05-03 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.957; 2013 IF: 2.269 |
Call Number |
UA @ lucian @ c:irua:109859 |
Serial |
2257 |
Permanent link to this record |
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|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Quantum-size effects on T-c in superconducting nanofilms |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
76 |
Issue |
3 |
Pages |
498-504 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Paris |
Editor |
|
Language |
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Wos |
000241434300022 |
Publication Date |
2006-09-21 |
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 |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
31 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.957; 2006 IF: 2.229 |
Call Number |
UA @ lucian @ c:irua:61463 |
Serial |
2788 |
Permanent link to this record |
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|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
Title |
Superconducting nanowires: quantum-confinement effect on the critical magnetic field and supercurrent |
Type |
A1 Journal article |
Year |
2009 |
Publication |
International journal of modern physics: B: condensed matter physics, statistical physics, applied physics
T2 – 32nd International Workshop on Condensed Matter Theories, Aug 12-19, 2008, Loughborough Univ, Loughborough, England |
Abbreviated Journal |
Int J Mod Phys B |
Volume |
23 |
Issue |
20-21 |
Pages |
4257-4268 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
We study the effect of electron confinement on the superconducting-to-normal phase transition driven by a magnetic field and/or on the current-carrying state of the superconducting condensate in nanowires. Our investigation is based on a self-consistent numerical solution of the Bogoliubov-de Gennes equations. We show that in a parallel magnetic field and/or in the presence of supercurrent the transition from superconducting to normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magnetic field exhibits quantum-size oscillations with pronounced resonant enhancements. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
World scientific |
Place of Publication |
Singapore |
Editor |
|
Language |
|
Wos |
000274525500026 |
Publication Date |
2009-09-23 |
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 |
|
ISSN |
0217-9792;1793-6578; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.736 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.736; 2009 IF: 0.408 |
Call Number |
UA @ lucian @ c:irua:95673 |
Serial |
3362 |
Permanent link to this record |
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|
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Author |
Chen, Y.; Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Quantum cascades in nano-engineered superconductors : geometrical, thermal and paramagnetic effects |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
26 |
Pages |
265702 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of a parallel magnetic field on the orbital motion of electrons in high-quality superconducting nanowires resulting in a superconductor-to-normal transition which occurs through a cascade of jumps in the order parameter as a function of the magnetic field. Such cascades originate from the transverse size quantization that splits the conduction band into a series of subbands. Here, based on a numerical solution of the Bogoliubov-de Gennes equations for a hollow nanocylinder, we investigate how the quantum-size cascades depend on the confining geometry, i.e., by changing the cylinder radius R and its thickness d we cover the range from the nanowire-like to the nanofilm-like regime. The cascades are shown to become much less pronounced when increasing R/d, i.e., when the nanofilm-like regime is approached. When the temperature is non-zero they are thermally smoothed. This includes the spin-magnetic-field interaction which reduces the critical (depairing) parallel magnetic field H-c,H-parallel to but does not have any qualitative effect on the quantum cascades. From our calculations it is seen that the paramagnetic limiting field H-par significantly exceeds H-c,H-parallel to even in extremely narrow nanocylinders, i.e., when R, d are down to a few nanometers, and H-c,H-parallel to is only about 10% larger when switching-off the spin-magnetic-field interaction in this case. Both characteristic fields, H-c,H-parallel to and H-par, exhibit pronounced quantum-size oscillations. We demonstrate that the quantum cascades and the quantum-size oscillations survive in the presence of surface roughness. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
|
Wos |
000305640800014 |
Publication Date |
2012-06-07 |
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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the ESF-AQDJJ network. MDC acknowledges the support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:100281 |
Serial |
2773 |
Permanent link to this record |
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|
|
Author |
Chen, Y.; Hong-Yu, W.; Peeters, F.M.; Shanenko, A.A. |
Title |
Quantum-size effects and thermal response of anti-Kramer-Pesch vortex core |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
27 |
Issue |
27 |
Pages |
125701 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Since the 1960's it has been well known that the basic superconductive quantities can exhibit oscillations as functions of the thickness (diameter) in superconducting nanofilms (nanowires) due to the size quantization of the electronic spectrum. However, very little is known about the effects of quantum confinement on the microscopic properties of vortices. Based on a numerical solution to the Bogoliubov-de Gennes equations, we study the quantum-size oscillations of the vortex core resulting from the sequential interchange of the Kramer-Pesch and anti-Kramer-Pesch regimes with changing nanocylinder radius. The physics behind the anti-Kramer-Pesch anomaly is displayed by utilizing a semi-analytical Anderson approximate solution. We also demonstrate that the anti-Kramer-Pesch vortex core is robust against thermal smearing and results in a distinctive two-maxima structure in the local density of states, which can be used to identify the existence of the anti-Kramer-Pesch vortex. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000351294700018 |
Publication Date |
2015-03-09 |
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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundation of China under Grant No. NSFC-11304134, the Flemish Science Foundation (FWO-Vl), and the Methusalem program. AAS acknowledges the support of the Brazilian agencies CNPq (grants 307552/2012-8 and 141911/2012-3) and FACEPE (APQ-0589-1.05/08). WHY acknowledges the support of Scientific Research Fund of Zhejiang Provincial Education Department (Y201120994). ; |
Approved |
Most recent IF: 2.649; 2015 IF: 2.346 |
Call Number |
c:irua:125460 |
Serial |
2787 |
Permanent link to this record |
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|
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Author |
Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. |
Title |
Superconducting nanofilms : molecule-like pairing induced by quantum confinement |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
18 |
Pages |
185701-185701,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000303500900018 |
Publication Date |
2012-04-05 |
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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
26 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:98223 |
Serial |
3357 |
Permanent link to this record |
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Author |
Chen, Y.; Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
Title |
Superconducting nanowires: quantum confinement and spatially dependent Hartree-Fock potential |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
21 |
Issue |
43 |
Pages |
435701,1-435701,7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
It is well known that, in bulk, the solution of the Bogoliubovde Gennes equations is the same whether or not the HartreeFock term is included. Here the HartreeFock potential is position independent and so gives the same contribution to both the single-electron energies and the Fermi level (the chemical potential). Thus, the single-electron energies measured from the Fermi level (they control the solution) stay the same. This is not the case for nanostructured superconductors, where quantum confinement breaks the translational symmetry and results in a position-dependent HartreeFock potential. In this case its contribution to the single-electron energies depends on the relevant quantum numbers. We numerically solved the Bogoliubovde Gennes equations with the HartreeFock term for a clean superconducting nanocylinder and found a shift of the curve representing the thickness-dependent oscillations of the critical superconducting temperature to larger diameters. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000270642700012 |
Publication Date |
2009-10-09 |
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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
Call Number |
UA @ lucian @ c:irua:79162 |
Serial |
3360 |
Permanent link to this record |
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|
Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
Title |
Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
27 |
Pages |
275701 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
|
Wos |
000305653100012 |
Publication Date |
2012-06-21 |
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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:100280 |
Serial |
3793 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Vasenko, A.S.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
Title |
Influence of disorder on superconducting correlations in nanoparticles |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
Volume |
29 |
Issue |
29 |
Pages |
605-609 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate how the interplay of quantum confinement and level broadening caused by disorder affects superconducting correlations in ultra-small metallic grains. We use the electron-phonon interaction-induced electron mass renormalization and the reduced static-path approximation of the BCS formalism to calculate the critical temperature as a function of the grain size. We show how the strong electron-impurity scattering additionally smears the peak structure in the electronic density of states of a metallic grain and imposes additional limits on the critical temperature under strong quantum confinement. |
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 |
|
Language |
|
Wos |
000371089500013 |
Publication Date |
2016-01-08 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1557-1939 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.18 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Flemish Science Foundation (FWO-Vl), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO-Vl. ; |
Approved |
Most recent IF: 1.18 |
Call Number |
UA @ lucian @ c:irua:132286 |
Serial |
4195 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Mints, R.G.; Peeters, F.M. |
Title |
Andreev-type states induced by quantum confinement |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques |
Abbreviated Journal |
J Surf Investig-X-Ra |
Volume |
2 |
Issue |
4 |
Pages |
611-615 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
The properties of a clean superconductor with nanoscale dimensions are governed by quantum confinement of the electrons. This results in a spatially inhomogeneous superconducting condensate and in the formation of new Andreev-type quasiparticle states. These states are mainly located beyond regions where the superconducting condensate is enhanced. A numerical self-consistent solution of the Bogoliubov-de Gennes equations for a cylindrical metallic nanowire shows that these new Andreev-type states decrease the ratio of the energy gap to the critical temperature. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000262864600021 |
Publication Date |
2008-08-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1027-4510;1819-7094; |
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:75991 |
Serial |
113 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Vagov, A.; Peeters, F.M.; Aguiar, J.A. |
Title |
Nanofilms as effectively multiband superconductors: Intraband-pairing approximation and Ginzburg-Landau theory |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physica: B : condensed matter |
Abbreviated Journal |
Physica B |
Volume |
455 |
Issue |
|
Pages |
3-5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
It is well-known that the Ginzburg-Landau (GL) theory is a reliable and powerful theoretical tool to investigate the magnetic response of a superconducting state. However, in its standard form, this approach is not applicable to atomically uniform nano-thin superconducting films which are effective multiband superconductors. Here we discuss a relevant generalization of the GL theory, focusing on the underlying intraband-pairing approximation. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000344239200002 |
Publication Date |
2014-07-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4526; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.386 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-VI), and the Methusalem program. A.A.S. acknowledges the support of the Brazilian agencies CNPq and FACEPE (APQ-0589-1.05/08). ; |
Approved |
Most recent IF: 1.386; 2014 IF: 1.319 |
Call Number |
UA @ lucian @ c:irua:121192 |
Serial |
2256 |
Permanent link to this record |
|
|
|
Author |
Croitoru, M.D.; Zachmann, M.; Vagov, A.; Axt, V.M.; Shanenko, A.A.; Kettmann, P.; Papenkort, T.; Kuhn, T. |
Title |
Coherent dynamics of confinement-induced multiband superconductors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
503 |
Issue |
|
Pages |
183-186 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the coherent dynamics of pairing in a nanoscale superconductor, that is intrinsically multiband, after an external perturbation in the non-adiabatic regime. The description of the dynamics of the pairing order is within the density-matrix approach based on the BCS model and the Bogoliubov-de Gennes equations. We find that for certain resonant wire widths the superconducting order parameter exhibits two oscillatory frequencies which are determined by the long-time asymptotic values of the subgaps. This in turn leads to a pronounced beating phenomenon. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000340070600040 |
Publication Date |
2014-04-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
1 |
Open Access |
|
Notes |
; M.D.C. acknowledges the support from the Back to Belgium Grant of the federal Science Policy (BELSPO). ; |
Approved |
Most recent IF: 1.404; 2014 IF: 0.942 |
Call Number |
UA @ lucian @ c:irua:118745 |
Serial |
378 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Nanoscale superconductivity: nanowires and nanofilms |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
468 |
Issue |
7/10 |
Pages |
593-598 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000257355300021 |
Publication Date |
2008-03-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.404; 2008 IF: 0.740 |
Call Number |
UA @ lucian @ c:irua:69623 |
Serial |
2273 |
Permanent link to this record |
|
|
|
Author |
Peeters, F.M.; Croitoru, M.D.; Shanenko, A.A. |
Title |
Nanowires and nanofilms: superconductivity in quantum-size regime |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
468 |
Issue |
4 |
Pages |
326-330 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000254816500017 |
Publication Date |
2007-11-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.404; 2008 IF: 0.740 |
Call Number |
UA @ lucian @ c:irua:69621 |
Serial |
2283 |
Permanent link to this record |
|
|
|
Author |
Komendová, L.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M. |
Title |
The healing lengths in two-band superconductors in extended Ginzburg-Landau theory |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
479 |
Issue |
|
Pages |
126-129 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the vortex profiles in two-gap superconductors using the extended Ginzburg-Landau theory. The results shed more light on the disparity between the effective length scales in two bands. We compare the behavior expected from the standard Ginzburg-Landau theory with this new approach, and find good qualitative agreement in the case of LiFeAs. (C) 2011 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000308580600029 |
Publication Date |
2012-01-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; |
Approved |
Most recent IF: 1.404; 2012 IF: 0.718 |
Call Number |
UA @ lucian @ c:irua:101871 |
Serial |
3585 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Vagov, A.V.; Axt, V.M.; Perali, A.; Peeters, F.M. |
Title |
Atypical BCS-BEC crossover induced by quantum-size effects |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
86 |
Issue |
3 |
Pages |
033612 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantum-size oscillations of the basic physical characteristics of a confined fermionic condensate are a well-known phenomenon. Its conventional understanding is based on the single-particle physics, whereby the oscillations follow variations in the single-particle density of states driven by the size quantization. Here we present a study of a cigar-shaped ultracold superfluid Fermi gas, which demonstrates an important many-body aspect of the quantum-size coherent effects, overlooked previously. The many-body physics is revealed here in the atypical crossover from the Bardeen-Cooper-Schrieffer (BCS) superfluid to the Bose-Einstein condensate (BEC) induced by the size quantization of the particle motion. The single-particle energy spectrum for the transverse dimensions is tightly bound, whereas for the longitudinal direction it resembles a quasi-free dispersion. This results in the formation of a series of single-particle subbands (shells) so that the aggregate fermionic condensate becomes a coherent mixture of subband condensates. Each time when the lower edge of a subband crosses the chemical potential, the BCS-BEC crossover is approached in this subband, and the aggregate condensate contains both BCS and BEC-like components. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000308639500004 |
Publication Date |
2012-09-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
34 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). The authors thank C. Salomon and C. Vale for their valuable explications of the experimental situation and interest to our work. We are grateful to G. C. Strinati, D. Neilson, and P. Pieri for useful discussions. M. D. C. acknowledges support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). A. P. gratefully acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 4844 for his visit to the University of Antwerp. A. A. S. acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 5200 for his visit to the University of Camerino. ; |
Approved |
Most recent IF: 2.925; 2012 IF: 3.042 |
Call Number |
UA @ lucian @ c:irua:101844 |
Serial |
203 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A. |
Title |
Imperfect fermi gas : kinetic and interaction energies |
Type |
A1 Journal article |
Year |
2004 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
70 |
Issue |
6 |
Pages |
063618-13 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A uniform ground-state three-dimensional Fermi gas with short-range repulsive pairwise interaction is under consideration. Its kinetic and interaction energies are calculated up to the second order of the expansion in the gas parameter. Similar to recent results for an interacting Bose gas, the quantities in question are found to depend on the pairwise interaction through two characteristic lengths: the former, a, is the s-wave scattering length, and the latter, b, is related to a by b=a-m(partial derivativea/partial derivativem), where m stands for the fermion mass. To control the results, we proceed in two independent ways. The first involves the Hellmann-Feynman theorem applied to derive the kinetic and interaction energies from the total-energy expansion in the gas parameter first found by Huang and Yang. The second way operates with in-medium pair wave functions and allows one to calculate the quantities of interest “from scratch.” The results of the present investigation, taken together with those of the recent consideration of a dilute Bose gas, make it possible to conclude that the pairwise interaction in a quantum gas has an essential and nontrivial effect on the kinetic energy, which is not the case for a classical many-particle system. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000226418900116 |
Publication Date |
2004-12-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
2.925 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.925; 2004 IF: 2.902 |
Call Number |
UA @ lucian @ c:irua:103196 |
Serial |
1562 |
Permanent link to this record |
|
|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
Title |
Dependence of superconducting properties on the size and shape of a nanoscale superconductor: from nanowire to film |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
76 |
Issue |
|
Pages |
024511,1-6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000248496200104 |
Publication Date |
2007-07-18 |
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 |
54 |
Open Access |
|
Notes |
Fwo-Vi; Iap; Bof-Top |
Approved |
Most recent IF: 3.836; 2007 IF: 3.172 |
Call Number |
UA @ lucian @ c:irua:69655 |
Serial |
643 |
Permanent link to this record |
|
|
|
Author |
Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M. |
Title |
Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
6 |
Pages |
064522-064522,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000294226000013 |
Publication Date |
2011-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
56 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:92414 |
Serial |
695 |
Permanent link to this record |
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|
|
Author |
Vagov, A.V.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
Title |
Extended Ginzburg-Landau formalism : systematic expansion in small deviation from the critical temperature |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
1 |
Pages |
014502-014502,17 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Based on the Gor'kov formalism for a clean s-wave superconductor, we develop an extended version of the single-band Ginzburg-Landau (GL) theory by means of a systematic expansion in the deviation from the critical temperature T(c), i.e., tau = 1 – T/T(c). We calculate different contributions to the order parameter and the magnetic field: the leading contributions (proportional to tau(1/2) in the order parameter and. t in the magnetic field) are controlled by the standard GL theory, while the next-to-leading terms (proportional to tau(3/2) in the gap and proportional to tau(2) in the magnetic field) constitute the extended GL (EGL) approach. We derive the free-energy functional for the extended formalism and the corresponding expression for the current density. To illustrate the usefulness of our formalism, we calculate, in a semianalytical form, the temperature-dependent correction to the GL parameter at which the surface energy becomes zero, and analytically, the temperature dependence of the thermodynamic critical field. We demonstrate that the EGL formalism is not just a mathematical extension to the theory: variations of both the gap and the thermodynamic critical field with temperature calculated within the EGL theory are found in very good agreement with the full BCS results down to low temperatures, which dramatically improves the applicability of the formalism compared to its standard predecessor. |
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 |
000298985100002 |
Publication Date |
2012-01-10 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
36 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). A. V. V. is grateful to V. Zalipaev for important comments. A. A. S. thanks W. Pogosov for helpful notes. Discussions with E. H. Brandt and A. Perali are appreciated. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:96232 |
Serial |
1155 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Vagov, A.; Peeters, F.M. |
Title |
Giant drop in the Bardeen-Cooper-Schrieffer coherence length induced by quantum size effects in superconducting nanowires |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
10 |
Pages |
104524-104524,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The BCS coherence length in low-dimensional superconductors is dramatically modified by quantum-size effects. In particular, for nanowires made of conventional superconducting materials, we show that the longitudinal zero-temperature coherence length exhibits width-dependent drops by 23 orders of magnitude each time when the bottom of one of single-electron subbands formed due to the transverse quantization of electron motion is situated in a close vicinity to the Fermi level. This phenomenon has strong similarities to the well-known BCS-BEC (Bose-Einstein condensation) crossover in ultracold fermionic condensates but with an important exception: it is driven by the transverse quantization of the electron motion rather than by the externally controlled strength of the fermion-fermion interaction. |
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 |
000282269600005 |
Publication Date |
2010-09-29 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
29 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-network: INSTANS. M. D. C. acknowledges support from the Alexander von Humboldt Foundation. A. A. S. thanks R. G. Mints, W. V. Pogosov, D. Y. Vodolazov, A. Perali, and A. Bianconi for fruitful discussions. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:85419 |
Serial |
1337 |
Permanent link to this record |
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|
|
Author |
Orlova, N.V.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M.; Vagov, A.V.; Axt, V.M. |
Title |
Ginzburg-Landau theory for multiband superconductors : microscopic derivation |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
13 |
Pages |
134510-134518 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A procedure to derive the Ginzburg-Landau (GL) theory from the multiband BCS Hamiltonian is developed in a general case with an arbitrary number of bands and arbitrary interaction matrix. It combines the standard Gor'kov truncation and a subsequent reconstruction in order to match accuracies of the obtained terms. This reconstruction recovers the phenomenological GL theory as obtained from the Landau model of phase transitions but offers explicit microscopic expressions for the relevant parameters. Detailed calculations are presented for a three-band system treated as a prototype multiband superconductor. It is demonstrated that the symmetry in the coupling matrix may lead to the chiral ground state with the phase frustration, typical for systems with broken time-reversal symmetry. DOI: 10.1103/PhysRevB.87.134510 |
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 |
000317586700002 |
Publication Date |
2013-04-16 |
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 |
57 |
Open Access |
|
Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). A.A.S. acknowledges useful discussions with D. Neilson. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:108464 |
Serial |
1344 |
Permanent link to this record |
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|
|
Author |
Chen, Y.; Shanenko, A.A.; Peeters, F.M. |
Title |
Hollow nanocylinder: multisubband superconductivity induced by quantum confinement |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
13 |
Pages |
134523-134523:11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantization of the transverse electron motion in high-quality superconducting metallic nanowires and nanofilms results in the formation of well-distinguished single-electron subbands. They shift in energy with changing thickness, which is known to cause quantum-size superconducting oscillations. The formation of multiple subbands results in a multigap structure induced by the interplay between quantum confinement and Andreev mechanism. We investigate multisubband superconductivity in a hollow nanocylinder by numerically solving the Bogoliubov-de Gennes equations. When changing the inner radius and thickness of the hollow nanocylinder, we find a crossover from an irregular pattern of quantum-size superconducting oscillations, typical of nanowires, to an almost regular regime, specific for superconducting nanofilms. At this crossover the multigap structure becomes degenerate. The ratio of the critical temperature to the energy gap increases and approaches its bulk value while being reduced by 20-30% due to Andreev-type states driven by quantum confinement in the irregular regime. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
|
Wos |
000277207900098 |
Publication Date |
2010-04-26 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles Programme, Belgian States, Belgian Science Policy (IAP) and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:95623 |
Serial |
1481 |
Permanent link to this record |
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|
Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Magnetic-field induced quantum-size cascades in superconducting nanowires |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
2 |
Pages |
024505,1-9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000258190200105 |
Publication Date |
2008-07-03 |
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 |
42 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:70559 |
Serial |
1876 |
Permanent link to this record |
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|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
Title |
Metallic nanograins : spatially nonuniform pairing induced by quantum confinement |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
21 |
Pages |
214509-214509,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
It is well known that the formation of discrete electron levels strongly influences the pairing in metallic nanograins. Here, we focus on another effect of quantum confinement in superconducting grains that was not studied previously, i.e., spatially nonuniform pairing. This effect is very significant when single-electron levels form bunches and/or a kind of shell structure. We find that, in highly symmetric grains, the order parameter can exhibit variations with position by an order of magnitude. Nonuniform pairing is closely related to a quantum-confinement-induced modification of the pairing-interaction matrix elements and size-dependent pinning of the chemical potential to groups of degenerate or nearly degenerate levels. For illustrative purposes, we consider spherical metallic nanograins and also rectangular shapes. We show that the relevant matrix elements are, as a rule, enhanced in the presence of quantum confinement, which favors spatial variations of the order parameter, compensating the corresponding energy cost. The size-dependent pinning of the chemical potential further increases the spatial variation of the pair condensate. The role of nonuniform pairing is smaller in less symmetric confining geometries and/or in the presence of disorder. However, it always remains of importance when the energy spacing between discrete electron levels δ is approaching the scale of the bulk gap ΔB, i.e., δ>0.10.2 ΔB. |
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 |
000291310000006 |
Publication Date |
2011-06-06 |
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 |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
23 |
Open Access |
|
Notes |
; This work was supported by the Alexander von Humboldt Foundation, the Flemish Science Foundation (FWO-VI), and the Belgian Science Policy (IAP). M. D. C. acknowledges support of the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:90081 |
Serial |
2010 |
Permanent link to this record |
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Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Oscillations of the superconducting temperature induced by quantum well states in thin metallic films: numerical solution of the Bogoliubov-de Gennes equations |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
75 |
Issue |
1 |
Pages |
014519,1-9 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000243894600126 |
Publication Date |
2007-01-17 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
85 |
Open Access |
|
Notes |
Fwo-Vi; Bof-Top; Iap |
Approved |
Most recent IF: 3.836; 2007 IF: 3.172 |
Call Number |
UA @ lucian @ c:irua:63749 |
Serial |
2535 |
Permanent link to this record |