Holographic Stripes

TL;DR

This paper constructs inhomogeneous black hole solutions in AdS space that model spontaneous stripe formation in boundary field theories, revealing a second order phase transition influenced by axion coupling and exhibiting complex geometrical features.

Contribution

It introduces new inhomogeneous black hole solutions that demonstrate spontaneous translational symmetry breaking and detailed phase structure analysis.

Findings

Second order phase transition observed at large axion coupling.

Horizon geometry shows inhomogeneity and topological insulator features.

Low temperature horizons tend to pinch off.

Abstract

We construct inhomogeneous asymptotically AdS black hole solutions corresponding to the spontaneous breaking of translational invariance and the formation of striped order in the boundary field theory. We find that the system undergoes a second order phase transition in both the fixed density and fixed chemical potential ensembles, for sufficiently large values of the axion coupling. We investigate the phase structure as function of the temperature, axion coupling and the stripe width. The bulk solutions have striking geometrical features related to a magnetoelectric effect associated with the existence of a near horizon topological insulator. At low temperatures the horizon becomes highly inhomogeneous and tends to pinch off.}