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Josephson current in unconventional superconductors through an Anderson impurity

Y. Avishai·A. Golub
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Abstract

Josephson current for a system consisting of an Anderson impurity weakly coupled to two unconventional superconductors is studied and shown to be driven by a surface zero energy (mid-gap) bound-state. The repulsive Coulomb interaction in the dot can turn a $π$ junction into a 0-junction. This effect is more pronounced in p-wave superconductors while in high-temperature superconductors with $d_{x^2-y^2}$ symmetry it can exit for rather large artificial centers at which tunneling occurs within a finite region.

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BibTeXRIS

Y. Avishai, A. Golub. 1999-09-07. Josephson current in unconventional superconductors through an Anderson impurity. https://doi.org/10.1103/physrevb.61.11293

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