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The Coherence Field in the Field Perturbation Theory of Superconductivity

Moshe Dayan
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Abstract

We re-examine the Nambu-Gorkov perturbation theory of superconductivity on the basis of the Bogoliubov-Valatin quasi-particles. We show that two different fields (and two additional analogous fields) may be constructed, and that the Nambu field is only one of them. For the other field- the coherence field- the interaction is given by means of two interaction vertices that are based on the Pauli matrices tau1 and tau3. Consequently, the Hartree integral for the off-diagonal pairing self-energy may be finite, and in some cases large. We interpret the results in terms of conventional superconductivity, and also discuss briefly possible implications to HTSC.

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Moshe Dayan. 2006-07-23. The Coherence Field in the Field Perturbation Theory of Superconductivity. https://doi.org/10.1007/s10948-006-0134-2

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