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

J. C. Cuevas·W. Belzig
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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.

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J. C. Cuevas, W. Belzig. 2004-06-22. DC-transport in superconducting point contacts: a full counting statistics view. https://doi.org/10.1103/physrevb.70.214512

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