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arXiv · 1108.4683

Majorana modes in time-reversal invariant s-wave topological superconductors

Shusa Deng·Lorenza Viola·Gerardo Ortiz
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Abstract

We present a time-reversal invariant s-wave superconductor supporting Majorana edge modes. The multi-band character of the model together with spin-orbit coupling are key to realizing such a topological superconductor. We characterize the topological phase diagram by using a partial Chern number sum, and show that the latter is physically related to the parity of the fermion number of the time-reversal invariant modes. By taking the self-consistency constraint on the s-wave pairing gap into account, we also establish the possibility of a direct topological superconductor-to-topological insulator quantum phase transition.

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Shusa Deng, Lorenza Viola, Gerardo Ortiz. 2012-01-19. Majorana modes in time-reversal invariant s-wave topological superconductors. https://doi.org/10.1103/physrevlett.108.036803

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