Critical temperature of superconductors: Exact solution from Eliashberg equations on the weak-coupling side

Journal Article · Thu Nov 01 04:00:00 EST 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.42.7810· OSTI ID:6147145

Combescot, R ^[1]

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1. Laboratoire de Physique Statistique, Paris (France) Universite Pierre et Marie Curie, F-75231 Paris (France)

We solve exactly the Eliashberg equations for the critical temperature of a superconductor in the weak-coupling limit {lambda},{mu}{sup *}{r arrow}0 for a general Eliashberg function {alpha}{sup 2}{ital F}({omega}). We show that in this regime the best choice for the characteristic frequency is {omega}{sub log} in the sense that the dependence of {Tc} on the shape of {alpha}{sup 2}{ital F}({omega}) is optimally included in this way. However, there is an additional dependence of {ital T}{sub {ital c}} on the shape of {alpha}{sup 2}{ital F}({omega}), which is studied in detail. This leads to a uniform decrease of {ital T}{sub {ital c}} as the spectral width increases, for fixed {omega}{sub log}. We show that, in this weak-coupling regime, the critical temperature depends only on the large-scale structure of the spectrum.

• OSTI ID: 6147145
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 42:13; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

656100* -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CRITICAL TEMPERATURE
GORKOV-ELIASHBERG THEORY
HIGH-TC SUPERCONDUCTORS
MATHEMATICAL MODELS
NUCLEAR MODELS
NUMERICAL SOLUTION
PHYSICAL PROPERTIES
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
WEAK-COUPLING MODEL