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Comment on "Theory of Impure Superconductors: Anderson versus Abrikosov and Gor'kov"

R. J. Radtke
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Abstract

In a recent article, Kim and Overhauser [Phys. Rev. B 47, 8025 (1993)] have found fault with the theory of impure superconductors by Abrikosov and Gor'kov and have proposed an alternative formalism based on Green's functions which are not derivable from a Dyson equation. Although the corrections to the Abrikosov-Gor'kov theory found by Kim and Overhauser are correct for non-retarded interactions, I argue that these corrections do not appear when one treats realistic retarded interactions within the field-theoretic approach of Abrikosov and Gor'kov. Direct numerical computation of the impurity-induced suppression of the superconducting transition temperature Tc for both retarded and non-retarded interactions illustrates these points. I conclude that Abrikosov-Gor'kov theory applied to physical electron-electron interactions yields a tractable formalism which accurately predicts the effects of magnetic and non-magnetic impurities on Tc.

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R. J. Radtke. 1993-06-16. Comment on "Theory of Impure Superconductors: Anderson versus Abrikosov and Gor'kov". https://arxiv.org/abs/cond-mat/9306037

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