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arXiv · cond-mat/9712118

Anderson Model in a Superconductor: $Φ$-Derivable Theory

Ari T. Alastalo·Robert J. Joynt·Martti M. Salomaa
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Abstract

We introduce a new $Φ$-derivable approach for the Anderson impurity model in a BCS superconductor. The regime of validity of this conserving theory extends well beyond that of the Hartree-Fock approximation. This is the first generalization of the U-perturbation theory to encompass a superconductor.

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Ari T. Alastalo, Robert J. Joynt, Martti M. Salomaa. 1997-12-11. Anderson Model in a Superconductor: $Φ$-Derivable Theory. https://doi.org/10.1088/0953-8984%2F10%2F3%2F003

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