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Proceedings of the Physical Society

A Note on the Theory of Pairing Correlations

M R Bhagavan

Published Oct 1, 1963• 2 citations
Publisher

Abstract

It is shown that the Hartree-Bogolyubov theory of pairing correlations leads, in a clear and consistent manner, to a generalization of the Green function method of Gor'kov.
DOI
10.1088/0370-1328/82/4/320

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This chapter considers the analog of the time-dependent Hartree–Fock (mean-field) decoupling treated in Part I and extends it to the broken-symmetry phase for superfluid fermions. Two coupled equations for the “normal” and “anomalous” time-dependent single-particle Green’s functions are obtained, which extend to nonequilibrium situations the equations originally obtained at equilibrium by Gor’kov, soon after the BCS original article on the theory of superconductivity. Accordingly, the time-dependent gap (order) parameter is also introduced.