Communications in Theoretical Physics

On Theory of the Statistical Generating Functional for the Order Parameter (III) –Effective Action Formalism for the Order Parameter

Guangzhao Zhou, Zhao-Bin Su, Hao Bai-lin, Lu Yu

Published Jul 1, 1982• 3 citations

Abstract

A practical scheme is proposed in this paper to determine the quantum statistical properties of the order parameter in the frame work of the closed time-path Green's functions (CTPGF). As a microscopic quantum theory, this formalism is applicable in principle to both equilibrium and nonequilibrium phenomena and is capable of dealing with statistical systems both above and below their phase transition point. This formalism can be used to discuss the statistical properties of simple as well as composite order parameters in either uniform or nonuniform systems. As simple illustrations and check for the theory, the proposed prescription is applied to the contact-interaction model for superconductivity and a unimode laser system coupled with two-energy-level bound electrons.

DOI: 10.1088/0253-6102/1/4/389

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