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On the Lifshitz tail in the density of states of a superconductor with magnetic impurities

A. V. Balatsky·S. A. Trugman
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Abstract

We argue that any superconductor with magnetic impurities is gapless due to a Lifshitz tail in the density of states extending to zero energy. At low energy the density of states $ν(E \to 0)$ remains finite. We show that fluctuations in the impurity distribution produce regions of suppressed superconductivity, which are responsible for the low energy density of states.

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A. V. Balatsky, S. A. Trugman. 1997-05-09. On the Lifshitz tail in the density of states of a superconductor with magnetic impurities. https://doi.org/10.1103/physrevlett.79.3767

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