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Gap Fluctuations in Inhomogeneous Superconductors

Julia S. Meyer·B. D. Simons
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Abstract

Spatial fluctuations of the effective pairing interaction between electrons in a superconductor induce variations of the order parameter which in turn lead to significant changes in the density of states. In addition to an overall reduction of the quasi-particle energy gap, theory suggests that mesoscopic fluctuations of the impurity potential induce localised tail states below the mean-field gap edge. Using a field theoretic approach, we elucidate the nature of the states in the `sub-gap' region. Specifically, we show that these states are associated with replica symmetry broken instanton solutions of the mean-field equations.

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Julia S. Meyer, B. D. Simons. 2001-06-06. Gap Fluctuations in Inhomogeneous Superconductors. https://doi.org/10.1103/physrevb.64.134516

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