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arXiv · 0903.0421

Theory of heterotic SIS Josephson junctions between single- and multi-gap superconductors

Yukihiro Ota·Masahiko Machida·Tomio Koyama·Hideki Matsumoto
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Abstract

Using the functional integral method, we construct a theory of heterotic SIS Josephson junctions between single- and two-gap superconductors. The theory predicts the presence of in-phase and out-of-phase collective oscillation modes of superconducting phases. The former corresponds to the Josephson plasma mode whose frequency is drastically reduced for $\pm$ s-wave symmetry, and the latter is a counterpart of Leggett's mode in Josephson junctions. We also reveal that the critical current and the Fraunhofer pattern strongly depend on the symmetry type of the two-gap superconductor.

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Yukihiro Ota, Masahiko Machida, Tomio Koyama, Hideki Matsumoto. 2009-06-14. Theory of heterotic SIS Josephson junctions between single- and multi-gap superconductors. https://doi.org/10.1103/physrevlett.102.237003

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