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arXiv · 1012.5750

Real-time observation of discrete Andreev tunneling events

V. F. Maisi·O. -P. Saira·Yu. A. Pashkin·J. S. Tsai·D. V. Averin·J. P. Pekola
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Abstract

We provide a direct proof of two-electron Andreev transitions in a superconductor - normal metal tunnel junction by detecting them in a real-time electron counting experiment. Our results are consistent with ballistic Andreev transport with an order of magnitude higher rate than expected for a uniform barrier, suggesting that only part of the interface is effectively contributing to the transport. These findings are quantitatively supported by our direct current measurements in single-electron transistors with similar tunnel barriers.

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V. F. Maisi, O. -P. Saira, Yu. A. Pashkin, J. S. Tsai, D. V. Averin, J. P. Pekola. 2011-03-01. Real-time observation of discrete Andreev tunneling events. https://doi.org/10.1103/physrevlett.106.217003

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