Holographic non-Fermi liquid fixed points

TL;DR

This paper explores holographic duality techniques from string theory to analyze strongly-interacting fermionic systems, revealing non-Fermi liquid behavior with unique spectral properties linked to an AdS_2 gravitational region.

Contribution

It provides a detailed gravity calculation of the IR correlation function in holographic models, offering insights into non-Fermi liquid fixed points and their spectral characteristics.

Findings

Spectral functions exhibit non-Fermi liquid features.

Self-energy correlates with an AdS_2 IR fixed point.

Holographic models differ from Landau Fermi liquid theory.

Abstract

Techniques arising from string theory can be used to study assemblies of strongly-interacting fermions. Via this `holographic duality', various strongly-coupled many body systems are solved using an auxiliary theory of gravity. Simple holographic realizations of finite density exhibit single-particle spectral functions with sharp Fermi surfaces, of a form distinct from those of the Landau theory. The self-energy is given by a correlation function in an infrared fixed point theory which is represented by an AdS_2 region in the dual gravitational description. Here we describe in detail the gravity calculation of this IR correlation function. This article is a contribution to a special issue of Phil. Trans. A on the normal state of the cuprates; as such, we also provide some review and context.