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Ward identities for disordered metals and superconductors

Revaz Ramazashvili
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Abstract

This article revisits Ward identities for disordered interacting normal metals and superconductors. It offers a simple derivation based on gauge invariance and recasts the identities in a new form that allows easy analysis of the quasiparticle charge conservation (as e.g. in a normal metal) or non-conservation (as e.g. in a d-wave superconductor).

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Revaz Ramazashvili. 2002-10-31. Ward identities for disordered metals and superconductors. https://doi.org/10.1103/physrevb.66.220503

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