Eliashberg equations and superconductivity in a layered two-dimensional metal

Journal Article · Fri Oct 01 00:00:00 EDT 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.48.10504· OSTI ID:6072855

Malozovsky, Y M ^[1]; Bose, S M ^[2]; Longe, P ^[3]; Fan, J D ^[4]

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1. Department of Physics and Atmospheric Science, Drexel University, Philadelphia, Pennsylvania 19104 (United States) Department of Physics, Southern University and A M College, Baton Rouge, Louisiana 70813 (United States)
2. Department of Physics and Atmospheric Science, Drexel University, Philadelphia, Pennsylvania 19104 (United States)
3. Institut de Physique, B5, Universite de Liege, Sart-Tilman, B-4000 Liege (Belgium)
4. Department of Physics, Southern University and A M College, Baton Rouge, Louisiana 70813 (United States)

The Eliashberg equations for superconductivity in a layered two-dimensional (2D) metal, taking into account the interaction between an electron and an arbitrary boson excitation, are obtained. The theory is applied to the case of a plasmon-mediated electron-electron interaction and it is shown that the interelectronic Coulomb repulsion parameter [mu] is connected with both the bare Coulomb interaction and the single-particle excitation. An evaluation of this parameter shows that while remaining always positive, it decays with the decrease of the interlayer distance. It is also shown that the electron-plasmon interaction in a layered 2D system leads to a logarithmic divergence of the renormalization factor [ital Z]([omega]) as [omega][r arrow]0 and [ital T][r arrow]0. This gives rise to a logarithmic dependence of [lambda][sub pl], the electron-plasmon interaction constant, on temperature for [ital T][ge][ital T][sub [ital c]] and a logarithmic dependence on the gap parameter [Delta] for [ital T][much lt][ital T][sub [ital c]]. It is found that at small interlayer distance, i.e., for strong intelayer plasmon exchange, the cutoff frequency for plasmon exchange reaches its maximum value at the Fermi energy [var epsilon][sub [ital F]], which leads to the important conclusion that [ital T][sub [ital c]] is proportional to [var epsilon][sub [ital F]e][sup [minus]1/[lambda]][sub [ital e][ital f][ital f]].

• OSTI ID: 6072855
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 48:14; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

665411* -- Basic Superconductivity Studies-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COUPLING
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON-ELECTRON COUPLING
ELEMENTS
ENERGY GAP
GORKOV-ELIASHBERG THEORY
LAYERS
METALS
PHYSICAL PROPERTIES
PLASMONS
QUASI PARTICLES
RENORMALIZATION
SUPERCONDUCTIVITY
TEMPERATURE DEPENDENCE