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arXiv · 1809.05264

Strong Coupling Theory of Superconductivity

D. Rainer·J. A. Sauls
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Abstract

The electronic properties of correlated metals with a strong electron-phonon coupling may be understood in terms of a combination of Landau's Fermi-liquid theory and the strong-coupling theory of Migdal and Eliashberg. In these lecture notes we discuss the microscopic foundations of this phenomenological Fermi-liquid model of correlated, strong-coupling metals. We formulate the basic equations of the model, which are quasiclassical transport equations that describe both equilibrium and non-equilibrium phenomena for the normal and superconducting states of a metal. Our emphasis is on superconductors close to equilibrium, for which we derive the general linear response theory. As an application we calculate the dynamical conductivity of strong-coupling superconductors.

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D. Rainer, J. A. Sauls. 2018-09-14. Strong Coupling Theory of Superconductivity. https://doi.org/10.1142/9789814503891_0002

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