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arXiv · 1811.01746

Unconventional superconductivity in a doped quantum spin Hall insulator

Xianxin Wu·Mario Fink·Werner Hanke·Ronny Thomale·Domenico Di Sante
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Abstract

A monolayer of jacutingaite (Pt$_2$HgSe$_3$) has recently been identified as a novel quantum spin Hall insulator. By first-principles calculations, we study its Fermiology in the doped regime and unveil a type-I and type-II van Hove singularity for hole and electron doping, respectively. We find that the common link between the propensity for a topological band gap at pristine filling and unconventional superconductivity at finite doping roots in the longer ranged hybridization integrals on the honeycomb lattice. In a combined effort of random phase approximation and functional renormalization group, we find chiral $d$-wave order for the type-I and odd-parity $f$-wave order for the type-II regime.

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Xianxin Wu, Mario Fink, Werner Hanke, Ronny Thomale, Domenico Di Sante. 2018-11-05. Unconventional superconductivity in a doped quantum spin Hall insulator. https://doi.org/10.1103/physrevb.100.041117

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