Fermi liquid near a quantum critical point

TL;DR

This paper explores how Fermi liquid theory describes a metal approaching a quantum critical point of a Pomeranchuk instability, highlighting its strengths and limitations near criticality.

Contribution

It provides a detailed analysis of the applicability and boundaries of Fermi liquid theory in the vicinity of a quantum critical point.

Findings

Fermi liquid description becomes exact as temperature approaches zero.

Certain features of quantum criticality are captured within Fermi liquid theory.

Some aspects of the approach to quantum criticality lie outside Fermi liquid theory's scope.

Abstract

We investigate the approach to the quantum critical point of a Pomeranchuk instability from the symmetric, disordered side of the phase diagram. In the low-temperature limit, a Fermi liquid description of the metal is possible and becomes exact for T -> 0. We discuss in detail which features of the approach to quantum criticality can be captured within Fermi liquid theory and which are outside of its scope.