Microscopic theory of thermal phase slips in clean narrow superconducting wires

TL;DR

This paper provides an exact analytical solution for thermal phase slips in clean one-dimensional superconductors, deriving a closed-form free-energy barrier expression across all temperatures and currents.

Contribution

It introduces a microscopic model with exact solutions for saddle-point configurations, advancing understanding of thermal phase slips in superconducting wires.

Findings

Exact analytical solution for saddle-point configurations

Closed-form expression for free-energy barrier

Temperature and current dependence of phase-slip barriers

Abstract

We consider structure of a thermal phase-slip center for a simple microscopic model of a clean one-dimensional superconductors in which superconductivity occurs only within one conducting channel or several identical channels. Surprisingly, the Eilenberger equations describing the saddle-point configuration allow for exact analytical solution in the whole temperature and current range. This solution allows us to derive a closed expression for the free-energy barrier, which we use to compute its temperature and current dependences.