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Theory of the Josephson effect in superconductor / ferromagnet / superconductor junctions

Y. Tanaka·S. Kashiwaya
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Abstract

To reveal the influence of the exchange interaction on the Josephson effect, the d.c. Josephson current in unconventional-superconductor / ferromagnet / unconventional-superconductor junctions is studied. When the two superconductors have d-wave symmetry, the Josephson current is drastically suppressed with the increase of the exchange interaction. On the other hand, when the two superconductors have different parities, e.g. s-wave and p-wave, an enhancement of the Josephson current is obtained with the increment of the exchange interaction due to the break-down of SU(2) symmetry in the spin space.

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Y. Tanaka, S. Kashiwaya. 1999-03-09. Theory of the Josephson effect in superconductor / ferromagnet / superconductor junctions. https://arxiv.org/abs/cond-mat/9903034

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