Theory of heterotic superconductor-insulator-superconductor Josephson junctions between single- and multiple-gap superconductors.
Using the functional integral method, we construct a theory of heterotic superconductor-insulator-superconductor Josephson junctions between one- 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 +/- 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.
Ota
Yukihiro
Y
CCSE, Japan Atomic Energy Agency, Tokyo 110-0015, Japan.
Machida
Masahiko
M
Koyama
Tomio
T
Matsumoto
Hideki
H