DC-transport in superconducting point contacts: a full counting statistics view

TL;DR

This paper provides a comprehensive theoretical analysis of dc transport in superconducting point contacts using full counting statistics, revealing detailed insights into charge transfer and transport properties across various junction types.

Contribution

It introduces a full counting statistics approach to analyze dc transport in superconducting point contacts, covering diverse junction types and temperature effects.

Findings

Full counting statistics yields all cumulants of charge transfer.

Transport properties differ significantly from normal contacts.

Temperature influences cumulants and transport behavior.

Abstract

We present a comprehensive theoretical analysis of the dc transport properties of superconducting point contacts. We determine the full counting statistics for these junctions, which allows us to calculate not only the current or the noise, but all the cumulants of the current distribution. We show how the knowledge of the statistics of charge transfer provides an unprecedented level of understanding of the different transport properties for a great variety of situations. We illustrate our results with the analysis of junctions between BCS superconductors, contacts between superconductors with pair-breaking mechanisms and short diffusive bridges. We also discuss the temperature dependence of the different cumulants and show the differences with normal contacts.