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arXiv · 1912.04258

Fluctuation-induced odd-frequency spin-triplet pairing in disordered electron liquid

Vladimir A. Zyuzin·Alexander M. Finkel'stein
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Abstract

We consider a two-dimensional disordered conductor in the regime when the superconducting phase is destroyed by the magnetic field. We analyze a combination of fluctuations of different origin which results in an effective interaction amplitude suitable for a spontaneous s-wave odd-frequency pairing instability. We observe that the end point of the superconductivity is a quantum critical point separating the conventional superconducting phase from a state with the odd-frequency spin-triplet pairing instability. We speculate that this could shed light on a rather mysterious insulating state observed in strongly disordered superconducting films in a broad region of the magnetic fields.

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Vladimir A. Zyuzin, Alexander M. Finkel'stein. 2019-12-09. Fluctuation-induced odd-frequency spin-triplet pairing in disordered electron liquid. https://doi.org/10.1103/physrevb.105.214523

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