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arXiv · 1103.1930

Half-metallic Surface States and Topological Superconductivity in NaCoO$_2$ from first principles

Hongming Weng·Gang Xu·Haijun Zhang·Shou-Cheng Zhang·Xi Dai·Zhong Fang
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Abstract

Based on first-principles calculations, we predict a half-metallic surface state in layered bulk insulator NaCoO2, with tunable surface hole concentration. The half-metallic surface has a single Fermi surface with a helical spin texture, similar to the surface state of topological insulators, but with the key difference of time-reversal symmetry breaking in the present case. We propose the realization of topological superconductivity and Majorana fermions when the half-metallic surface states are in proximity contact with a conventional superconductor.

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Hongming Weng, Gang Xu, Haijun Zhang, Shou-Cheng Zhang, Xi Dai, Zhong Fang. 2011-09-01. Half-metallic Surface States and Topological Superconductivity in NaCoO$_2$ from first principles. https://doi.org/10.1103/physrevb.84.060408

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