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arXiv · 0809.3343

Broken time-reversal symmetry in Josephson junction involving two-band superconductors

T. K. Ng·N. Nagaosa
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Abstract

A novel time-reversal symmetry breaking state is found theoretically in the Josephson junction between the two-gap superconductor and the conventional s-wave superconductor. This occurs due to the frustration between the three order parameters analogous to the two antiferromagnetically coupled XY-spins put under a magnetic field. This leads to the interface states with the energies inside the superconducting gap. Possible experimental observations of this state with broken time-reversal symmetry are discussed.

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T. K. Ng, N. Nagaosa. 2008-09-19. Broken time-reversal symmetry in Josephson junction involving two-band superconductors. https://doi.org/10.1209/0295-5075/87/17003

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