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arXiv:cond-mat/9706033

Functional Integral approach to quasi-particles in Fermi Liquid theory

Tai Kai Ng

Published Jun 4, 1997• 1 citation
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Abstract

In this paper we propose a new way of organizing many-body perturbation theory in the Path-integral formulation where a set of quasi-particle wave-functionals $ψ$'s are introduced and are identified with quasi-particles in Landau Fermi liquid theory. We show how Fermi liquid theory can be obtained through $ψ$'s in this new framework of perturbation theory, where the only assumption is adiabaticity between non-interacting and interacting states and the quasi-particle renormalization factor z does not appear explicitly. Consequences of our new formulation are discussed.

DOI
10.48550/arxiv.cond-mat/9706033

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In this paper we propose a new way of organizing many-body perturbation theory in the Path-integral formulation where a set of quasi-particle wave-functionals ψψψ's are introduced and are identified with quasi-particles in Landau Fermi liquid theory. We show how Fermi liquid theory can be obtained through ψψψ's in this new framework of perturbation theory, where the only assumption is adiabaticity between non-interacting and interacting states and the quasi-particle renormalization factor z does not appear explicitly. Consequences of our new formulation are discussed.
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U(1)U(1)U(1) Fermi liquid theory - A Fermi liquid state that supports exclusion statistics
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