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arXiv · 1709.06638

Time-reversal symmetry breaking phase and gapped surface states in d-wave nanoscale superconductors

Yuki Nagai·Yukihiro Ota·K. Tanaka
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Abstract

We solve the Bogoliubov-de Gennes equations self-consistently for d-wave superconductors with [110] surfaces. We find spontaneous breaking of time-reversal symmetry (TRS) caused by the spontaneous occurrence of a complex order parameter with an extended s-wave symmetry along the [110] surfaces. In the TRS-breaking phase, the d-wave order parameter itself becomes complex. We also show that vortex-antivortex pairs can appear along the [110] surfaces of nanoribbons. These pairs are detectable with surface sensitive probes.

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Yuki Nagai, Yukihiro Ota, K. Tanaka. 2017-09-19. Time-reversal symmetry breaking phase and gapped surface states in d-wave nanoscale superconductors. https://doi.org/10.1088/1742-6596%2F969%2F1%2F012039

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