Holographic sliding stripes

TL;DR

This paper investigates the transport properties of a holographic model with spontaneous stripe order, revealing how sliding stripes and broken translation symmetry affect conductivities in inhomogeneous systems.

Contribution

It provides a detailed analysis of both DC and AC conductivities in a defect CFT with spontaneous stripe order, highlighting the effects of broken translation symmetry and spatial modulation.

Findings

Stripe sliding causes a Goldstone mode affecting conductivity.

Spatially modulated magnetization current complicates horizon-based conductivity calculations.

Ground state features combined spin and charge density waves.

Abstract

Holographic models provide unique laboratories to investigate non-linear physics of transport in inhomogeneous systems. We provide a detailed account of both DC and AC conductivities in a defect CFT with spontaneous stripe order. The spatial symmetry is broken at large chemical potential and the resulting ground state is a combination of a spin and charge density wave. An infinitesimal applied electric field across the stripes will cause the stripes to slide over the underlying density of smeared impurities, a phenomenon which can be associated with the Goldstone mode for the spontaneously broken translation symmetry. We show that the presence of a spatially modulated background magnetization current thwarts the expression of some DC conductivities in terms of horizon data.