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Andreev reflection in layered structures: implications for high T_c grain boundary Josephson junctions

A. A. Golubov·F. Tafuri
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Abstract

Andreev reflection is investigated in layered anisotropic normal metal / superconductor (N/S) systems in the case of an energy gap Δin S not negligible with respect to the Fermi energy E_F, as it probably occurs with high critical temperature superconductors (HTS). We find that in these limits retro-reflectivity, which is a fundamental feature of Andreev reflection, is broken modifying sensitively transport across S/N interfaces. We discuss the consequences for supercurrents in HTS Josephson junctions and for the midgap states in S-N contacts

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A. A. Golubov, F. Tafuri. 2000-10-06. Andreev reflection in layered structures: implications for high T_c grain boundary Josephson junctions. https://doi.org/10.1103/physrevb.62.15200

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