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General transport properties of superconducting quantum point contacts: a Green functions approach

A. Martin-Rodero·A. Levy Yeyati·J. C. Cuevas
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Abstract

We discuss the general transport properties of superconducting quantum point contacts. We show how these properties can be obtained from a microscopic model using nonequilibrium Green function techniques. For the case of a one-channel contact we analyze the response under different biasing conditions: constant applied voltage, current bias and microwave-induced transport. Current fluctuations are also analyzed with particular emphasis on thermal and shot-noise. Finally, the case of superconducting transport through a resonant level is discussed. The calculated properties show a remarkable agreement with the available experimental data from atomic-size contacts measurements. We suggest the possibility of extending this comparison to several other predictions of the theory.

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A. Martin-Rodero, A. Levy Yeyati, J. C. Cuevas. 1998-11-19. General transport properties of superconducting quantum point contacts: a Green functions approach. https://doi.org/10.1006/spmi.1999.0744

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