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arXiv · 1605.07179

No-go theorem for a time-reversal invariant topological phase in noninteracting systems coupled to conventional superconductors

Arbel Haim·Erez Berg·Karsten Flensberg·Yuval Oreg
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Abstract

We prove that a system of non-interacting electrons proximity coupled to a conventional s-wave superconductor cannot realize a time reversal invariant topological phase. This is done by showing that for such a system, in either one or two dimensions, the topological invariant of the corresponding symmetry class (DIII) is always trivial. Our results suggest that the pursuit of Majorana bound states in time-reversal invariant systems should be aimed at interacting systems or at proximity to unconventional superconductors.

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Arbel Haim, Erez Berg, Karsten Flensberg, Yuval Oreg. 2016-10-19. No-go theorem for a time-reversal invariant topological phase in noninteracting systems coupled to conventional superconductors. https://doi.org/10.1103/physrevb.94.161110

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