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arXiv · 0903.5102

Broken translational and time-reversal symmetry in superconducting films

A. B. Vorontsov
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Abstract

We demonstrate that films of unconventional (d-wave) superconductor at temperatures $T\lesssim 0.43 T_c$ can exhibit unusual superconducting phases. The new ground states beside the broken gauge and the point group symmetries can spontaneously break (i) continuous translational symmetry and form periodic order parameter structures in the plane of the film, or (ii) time-reversal symmetry and develop supercurrent flowing along the film. These states are result of the strong transverse inhomogeniety present in films with thickness of several coherence lengths. We show a natural similarity between formation of these states and the Fulde-Ferrell-Larkin-Ovchinnikov state.

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A. B. Vorontsov. 2009-03-29. Broken translational and time-reversal symmetry in superconducting films. https://doi.org/10.1103/physrevlett.102.177001

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