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 (midgap) bound state. The repulsive Coulomb interaction in the dot can turn a (Formula presented) junction into a 0 junction. This effect is more pronounced in p-wave superconductors while in high-temperature superconductors with (Formula presented) symmetry it can exist for rather large artificial centers at which tunneling occurs within a finite region.
|Number of pages||4|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - 1 Jan 2000|