Holographic models of non-Fermi liquid metals revisited: an effective field theory approach

TL;DR

This paper develops a new holographic model for strongly coupled metals that accurately captures Fermi surface properties and satisfies Luttinger's theorem, addressing previous model limitations.

Contribution

It introduces a novel approach to holographic modeling of metals by focusing on the effective field theory of IR physics, ensuring physically realistic features.

Findings

Holographic model reproduces Fermi surface with Luttinger's theorem

Model exhibits physically reasonable IR properties

Addresses previous drawbacks of holographic metal models

Abstract

Accessing the physics of strongly coupled metals in a controlled way is a challenging problem in theoretical condensed matter physics. In this paper, we revisit the possibility of understanding strongly coupled metals through a holographic duality with a weakly coupled gravitational theory in one higher dimension (i.e.\ a suitable generalization of the "AdS/CFT duality". Previous attempts at devising holographic models of strongly coupled metals have suffered from severe drawbacks; for example, they do not even seem to be able to describe a Fermi surface that satisfies Luttinger's theorem, which is ought to be a core requirement in any physically reasonable model of a metal. Here, we propose a radically different approach to constructing holographic models of strongly coupled metals. The idea is that for applications, it should be sufficient to construct a holographic dual of the effective field theory that controls the infra-red physics of the metal. We invoke recent work that has identified a precise criterion for such an effective field theory to be "emergeable" from a continuum ultra-violet (UV) theory at nonzero charge density (or its equivalent in lattice models, namely an incommensurate charge filling). We show that imposing this criterion leads to a holographic model of a strongly coupled metal with physically reasonable properties, including a Fermi surface satisfying Luttinger's theorem. We discuss a possible physical interpretation of our results.