Critical current of a superconducting wire via gauge/gravity duality

TL;DR

This paper uses gauge/gravity duality to analyze the behavior of thin superconducting wires at finite current, revealing that the normal state is unstable and superconductivity emerges at zero temperature.

Contribution

It introduces a novel application of gauge/gravity duality to model superconducting nanowires, connecting string theory constructs with condensed matter phenomena.

Findings

Normal state is always unstable at zero temperature.

Superconducting component appears spontaneously.

Results relate to experimental switching current statistics.

Abstract

We describe application of the gauge/gravity duality to study of thin superconducting wires at finite current. The large number N of colors of the gauge theory is identified with the number of filled transverse channels in the wire. On the gravity side, the physics is described by a system of D3 and D5 branes intersecting over a line. We consider the ground state of the system at fixed electric current and find that at zero temperature the normal state is always unstable with respect to appearance of a superconducting component. We discuss relation of our results to recent experiments on statistics of the switching current in nanowires.