Magnetic Response in the Holographic Insulator/Superconductor Transition

TL;DR

This paper investigates the magnetic and Aharonov-Bohm responses of holographic insulator/superconductor transitions, revealing that insulators exhibit stronger effects than conductors, with implications for supersolid behavior.

Contribution

It introduces a holographic model of insulator/superconductor transition analyzing magnetic and Aharonov-Bohm effects, highlighting stronger effects in insulators and linking to supersolid properties.

Findings

Magnetic fields induce vortices, indicating type II superconductivity.

Insulators show unsuppressed Aharonov-Bohm effects compared to conductors.

Holographic insulators can be interpreted as supersolids with strong quantum effects.

Abstract

We study the magnetic response of holographic superconductors exhibiting an insulating "normal" phase. These materials can be realized as a CFT compactified on a circle, which is dual to the AdS Soliton geometry. We study the response under i) magnetic fields and ii) a Wilson line on the circle. Magnetic fields lead to formation of vortices and allows one to infer that the superconductor is of type II. The response to a Wilson line is in the form of Aharonov-Bohm-like effects. These are suppressed in the holographic conductor/superconductor transition but, instead, they are unsuppressed for the insulator case. Holography, thus, predicts that generically insulators display stronger Aharonov-Bohm effects than conductors. In the fluid-mechanical limit the AdS Soliton is interpreted as a supersolid. Our results imply that supersolids display unsuppressed Aharonov-Bohm (or "Sagnac") effects - stronger than in superfluids.