Gravity dual of spin and charge density waves

TL;DR

This paper explores the gravity dual of charge and spin density waves in a holographic model, revealing a phase transition from a homogeneous state to a spatially modulated density wave at high charge density.

Contribution

It identifies the end point of an instability in the D3-D7' model, demonstrating the emergence of a charge and spin density wave as a new ground state.

Findings

Homogeneous state becomes unstable at high charge density.

A spatially modulated charge and spin density wave forms as the ground state.

Phase transition from homogeneous to modulated state is first order, with a second-order critical point at zero magnetic field.

Abstract

At high enough charge density, the homogeneous state of the D3-D7' model is unstable to fluctuations at nonzero momentum. We investigate the end point of this instability, finding a spatially modulated ground state, which is a charge and spin density wave. We analyze the phase structure of the model as a function of chemical potential and magnetic field and find the phase transition from the homogeneous state to be first order, with a second-order critical point at zero magnetic field.