Switching current distributions in superconducting nanostrips

TL;DR

This paper investigates the statistical distribution of switching currents in superconducting nanostrips through theoretical and numerical methods, aiming to understand the microscopic mechanisms behind the switching behavior.

Contribution

It introduces a comprehensive analysis of switching current distributions using models and simulations, enabling extraction of transition rates across various conditions.

Findings

Switching current distributions depend on sweep rate, temperature, and material properties.

Simulations show how to combine data for different sweep rates to determine switching rates.

The study links distribution analysis to microscopic switching mechanisms.

Abstract

We study switching current distributions in superconducting nanostrips using theoretical models and numerical simulations. Switching current distributions are commonly measured in experiments and may provide a window into the microscopic switching mechanisms. As the current through a superconducting strip is increased from zero it will at some point switch to the normal dissipative state. Due to thermal and/or quantum fluctuations the switching current will be random and follow a certain distribution depending on sweep rate, temperature, material properties and geometry. By analyzing the resulting distribution it is possible to infer the transition rate for a switch, which can be related to the free energy barrier separating the metastable superconducting state and the normal one. We study different switching scenarios and show using simulations how data taken for different sweep rates can be combined to obtain the switching rate over a wider interval of currents.