Pomeranchuk instabilities in holographic metals

TL;DR

This paper introduces a holographic method to identify nematic phase instabilities in strongly coupled metals by adapting the Pomeranchuk technique within a curved AdS bulk, revealing stable and unstable regions in the phase diagram.

Contribution

It develops a novel holographic approach to detect Pomeranchuk instabilities in strongly coupled metallic systems using a curved AdS bulk framework.

Findings

Identified a wide stable parameter region in the phase diagram.

Mapped the unstable modes to nematic phase instabilities.

Explored effects of fermion mass and chemical potential on stability.

Abstract

We develop a method to detect instabilities leading to nematic phases in strongly coupled metallic systems. We do so by adapting the well-known Pomeranchuk technique to a weakly coupled system of fermions in a curved asymptotically AdS bulk. The resulting unstable modes are interpreted as corresponding to instabilities on the dual strongly coupled holographic metal. We apply our technique to a relativistic $3+1$-dimensional bulk with generic quartic fermionic couplings, and explore the phase diagram at zero temperature for finite values of the fermion mass and chemical potential, varying the couplings. We find a wide region of parameters where the system is stable, which is simply connected and localized around the origin of coupling space.