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Tail states in superconductors with weak magnetic impurities

I. Vekhter·A. V. Shytov·I. A. Gruzberg·A. V. Balatsky
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Abstract

We analyse the behavior of the density of states in a singlet s-wave superconductor with weak magnetic impurities in the clean limit by using the method of optimal fluctuation. We show that the density of states varies as $\ln N(E)\propto -|E-Δ_0|^{(7-d)/4}$ near the mean field gap edge $Δ_0$ in a d-dimensional superconductor. The optimal fluctuation in d>1 is strongly anisotropic. We compare the density of states with that obtained in other recent approaches.

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I. Vekhter, A. V. Shytov, I. A. Gruzberg, A. V. Balatsky. 2002-10-25. Tail states in superconductors with weak magnetic impurities. https://doi.org/10.1016/s0921-4526(02)02372-4

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