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Effect of spatial variations of superconducting gap on suppression of the transition temperature by impurities

M. E. Zhitomirsky·M. B. Walker
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Abstract

We calculate correction to the critical temperature of a dirty superconductor, which results from the local variations of the gap function near impurity sites. This correction is of the order of T_c/E_F and becomes important for short-coherence length superconductors. It generally reduces a pair-breaking effect. In s-wave superconductors small amounts of nonmagnetic impurities can increase the transition temperature.

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M. E. Zhitomirsky, M. B. Walker. 1998-02-04. Effect of spatial variations of superconducting gap on suppression of the transition temperature by impurities. https://doi.org/10.1103/physrevlett.80.5413

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