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arXiv · 1708.06755

DIII Topological Superconductivity with Emergent Time-Reversal Symmetry

Christopher Reeg·Constantin Schrade·Jelena Klinovaja·Daniel Loss
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Abstract

We find a new class of topological superconductors which possess an emergent time-reversal symmetry that is present only after projecting to an effective low-dimensional model. We show that a topological phase in symmetry class DIII can be realized in a noninteracting system coupled to an $s$-wave superconductor only if the physical time-reversal symmetry of the system is broken, and we provide three general criteria that must be satisfied in order to have such a phase. We also provide an explicit model which realizes the class DIII topological superconductor in 1D. We show that, just as in time-reversal invariant topological superconductors, the topological phase is characterized by a Kramers pair of Majorana fermions that are protected by the emergent time-reversal symmetry.

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Christopher Reeg, Constantin Schrade, Jelena Klinovaja, Daniel Loss. 2017-08-22. DIII Topological Superconductivity with Emergent Time-Reversal Symmetry. https://doi.org/10.1103/physrevb.96.161407

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