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arXiv · 1905.11584

Topological Superconductivity Intertwined with Broken Symmetries

Hui-Ke Jin·Dong-Hui Xu·Yi Zhou
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Abstract

Recently the superconductor and topological semimetal PbTaSe$_2$ was experimentally found to exhibit surface-only lattice rotational symmetry breaking below $T_c$. We exploit the Ginzburg-Landau free energy and propose a microscopic two-channel model to study possible superconducting states on the surface of PbTaSe$_2$. We identify two types of topological superconducting states. One is time-reversal invariant and preserves the lattice hexagonal symmetry while the other breaks both symmetries. We find that such time-reversal symmetry breaking is unavoidable for a superconducting state in a two dimensional irreducible representation of crystal point group in a system where the spatial inversion symmetry is broken and the strong spin-orbit coupling is present. Our findings will guide the search for topological chiral superconductors.

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Hui-Ke Jin, Dong-Hui Xu, Yi Zhou. 2019-05-28. Topological Superconductivity Intertwined with Broken Symmetries. https://arxiv.org/abs/1905.11584

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