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arXiv · 1306.2313

Time reversal symmetry breakdown in normal and superconducting states in frustrated three-band systems

Troels Bojesen·Egor Babaev·Asle Sudbø
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Abstract

We discuss the phase diagram and phase transitions in $U(1)\times \groupZ{2}$ three-band superconductors with broken time reversal symmetry. We find that beyond mean field approximation and for sufficiently strong frustration of interband interactions there appears an unusual metallic state precursory to a superconducting phase transition. In that state, the system is not superconducting. Nonetheless, it features a spontaneously broken $\groupZ{2}$ time reversal symmetry. By contrast, for weak frustration of interband coupling the energy of a domain wall between different $\groupZ{2}$ states is low and thus fluctuations restore broken time reversal symmetry in the superconducting state at low temperatures.

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Troels Bojesen, Egor Babaev, Asle Sudbø. 2013-06-10. Time reversal symmetry breakdown in normal and superconducting states in frustrated three-band systems. https://doi.org/10.1103/physrevb.88.220511

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