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Why does a metal-superconductor junction have a resistance?

C. W. J. Beenakker
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Abstract

This is a tutorial article based on a lecture delivered in June 1999 at the NATO Advanced Study Institute in Ankara. The phenomenon of Andreev reflection is introduced as the electronic analogue of optical phase-conjugation. In the optical problem, a disordered medium backed by a phase-conjugating mirror can become completely transparent. Yet, a disordered metal connected to a superconductor has the same resistance as in the normal state. The resolution of this paradox teaches us a fundamental difference between phase conjugation of light and electrons.

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C. W. J. Beenakker. 2007-04-22. Why does a metal-superconductor junction have a resistance?. https://doi.org/10.1007/978-94-011-4327-1_4

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