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arXiv · 1803.05571

Possible Chiral Topological Superconductivity in CrO$_{2}$ bilayers

Xu Dou·Kangjun Seo·Bruno Uchoa
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Abstract

We address the possible emergence of spin triplet superconductivity in CrO$_{2}$ bilayers, which are half-metals with fully spin-polarized conducting bands. Starting from a lattice model, we show that chiral $p+ip$ states compete with non-chiral $p$-wave ones. At large doping, the $p+ip$ channel has a sequence of topological phase transitions that can be tuned by gating effects and interaction strength. Among several phases, we find chiral topological phases having a single Majorana mode at the edge. We show that different topological superconducting phases could spontaneously emerge in the vicinity of the van-Hove singularities of the band.

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Xu Dou, Kangjun Seo, Bruno Uchoa. 2019-02-04. Possible Chiral Topological Superconductivity in CrO$_{2}$ bilayers. https://doi.org/10.1103/physrevb.99.104503

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