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arXiv · 1504.00155

Surface instability in nodal noncentrosymmetric superconductors

Carsten Timm·Stefan Rex·P. M. R. Brydon
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Abstract

We study the stability of topologically protected zero-energy flat bands at the surface of nodal noncentrosymmetric superconductors, accounting for the alteration of the gap near the surface. Within a selfconsistent mean-field theory, we show that the flat bands survive in a broad temperature range below the bulk transition temperature. There is a second transition at a lower temperature, however, below which the system spontaneously breaks time-reversal symmetry. The surface bands are shifted away from zero energy and become weakly dispersive. Simultaneously, a spin polarization and an equilibrium charge current develop in the surface region.

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Carsten Timm, Stefan Rex, P. M. R. Brydon. 2015-05-13. Surface instability in nodal noncentrosymmetric superconductors. https://doi.org/10.1103/physrevb.91.180503

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