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arXiv · 1309.1214

Time-Reversal-Symmetry-Broken State in the BCS Formalism for a Multi-Band Superconductor

Brendan J. Wilson·Mukunda P. Das
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Abstract

In three-band BCS superconductors with repulsive interband interactions, frustration between the bands can lead to an inherently complex gap function, arising out of a phase difference between the bands in the range 0 and π. Since the complex conjugate of this state is also a solution, the ground state is degenerate, and there appears a time-reversal-symmetry-broken state. In this paper we investigate the existence of this state as a function of interband coupling strength and show how a new phase transition appears between the TRSB and conventional BCS states.

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Brendan J. Wilson, Mukunda P. Das. 2013-09-05. Time-Reversal-Symmetry-Broken State in the BCS Formalism for a Multi-Band Superconductor. https://doi.org/10.1088/0953-8984%2F25%2F42%2F425702

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