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arXiv · 1402.4433

Two-dimensional time-reversal-invariant topological superconductivity in a doped quantum spin Hall insulator

Jing Wang·Yong Xu·Shou-Cheng Zhang
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Abstract

Time-reversal-invariant topological superconductors have a full paring gap in the bulk and gapless Majorana states at the edge or on the surface. Here, we theoretically propose topological superconductivity in a doped quantum spin Hall insulator. We study the pairing symmetry of doped Sn$X$ film within a two-orbital model, and show that it realizes a topological superconductor when the intraorbital attractive interaction is stronger than the interorbital interaction, which is generic for a doped quantum spin Hall insulator with strong spin-orbit coupling. Edge channels are studied in a tight-binding model numerically. Finally, we discuss the possible topological superconductivity in Sn$X$ film by comparing to $3d$ superconductivity in bulk Sn.

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Jing Wang, Yong Xu, Shou-Cheng Zhang. 2014-02-18. Two-dimensional time-reversal-invariant topological superconductivity in a doped quantum spin Hall insulator. https://doi.org/10.1103/physrevb.90.054503

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