Nonlinear $σ$ model for disordered superconductors

I. V. Yurkevich; Igor V. Lerner

doi:10.1103/physrevb.63.064522

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arXiv · cond-mat/0006378

Nonlinear $σ$ model for disordered superconductors

I. V. Yurkevich·Igor V. Lerner

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Abstract

We suggest a novel nonlinear $σ$-model for the description of disordered superconductors. The main distinction from existing models lies in the fact that the saddle point equation is solved non-perturbatively in the superconducting pairing field. It allows one to use the model both in the vicinity of the metal-superconductor transition and well below its critical temperature with full account for the self-consistency conditions. We show that the model reproduces a set of known results in different limiting cases, and apply it for a self-consistent description of the proximity effect at the superconductor-metal interface.

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I. V. Yurkevich, Igor V. Lerner. 2001-06-29. Nonlinear $σ$ model for disordered superconductors. https://doi.org/10.1103/physrevb.63.064522

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