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Andreev Bound States and Josephson Coupling in YBCO/Pb tunnel junction

J. Lesueur·X. Grison·M. Aprili·T. Kontos
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Abstract

We have made in-situ [103] and [110]YBCO/Pb junctions, which display an hysteretic behaviour with both a well-defined Quasi-Particule branch and a Josephson current. A zero energy conductance peak is observed in the tunneling conductance which is a signature of Andreev Bound States (ABS) at a surface of a d-wave superconductor. The observed splitting of this peak at low temperature may confirm the existence of a surface state which breaks time-reversal symmetry. However, up to now, we have not seen any evidence of a coupling between Josephson current and the zero-energy ABS, predicted by Y. Tanaka and S. Kashiwaya (PRB 56 p.892).

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J. Lesueur, X. Grison, M. Aprili, T. Kontos. 1999-09-14. Andreev Bound States and Josephson Coupling in YBCO/Pb tunnel junction. https://arxiv.org/abs/cond-mat/9909212

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