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arXiv · cond-mat/9812175

Shot noise and coherent multiple charge transfer in superconducting quantum point-contacts

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

We analyze the shot noise in a voltage biased superconducting quantum point-contact. Results are presented for the single channel case with arbitrary transmission. In the limit of very low transmission it is found that the effective charge, defined from the noise-current ratio, exhibits a step-like behavior as a function of voltage with well defined plateaus at integer values of the electronic charge. This multiple charge corresponds to the transmitted charge in a Multiple Andreev Reflection (MAR) process. This effect gradually disappears for increasing transmission due to interference between different MAR processes.

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J. C. Cuevas, A. Martin-Rodero, A. Levy Yeyati. 1998-12-10. Shot noise and coherent multiple charge transfer in superconducting quantum point-contacts. https://doi.org/10.1103/physrevlett.82.4086

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