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arXiv · 1011.6422

Topological superconductivity and Majorana fermions in half-metal / superconductor heterostructure

Suk Bum Chung·Hai-Jun Zhang·Xiao-Liang Qi·Shou-Cheng Zhang
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Abstract

As a half-metal is spin-polarized at its Fermi level by definition, it was conventionally thought to have little proximity effect to an s-wave superconductor. Here we show that, with interface spin-orbit coupling, $p_x +ip_y$ superconductivity without spin degeneracy is induced on the half-metal, and we give an estimate of its bulk energy gap. Therefore a single-band half-metal can give us a topological superconductor with a single chiral Majorana edge state. Our band calculation shows that two atomic layers of VTe or CrO$_2$ is a single-band half-metal for a wide range ($\sim$0.1eV) of Fermi energy and thus is a suitable candidate material.

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Suk Bum Chung, Hai-Jun Zhang, Xiao-Liang Qi, Shou-Cheng Zhang. 2011-02-08. Topological superconductivity and Majorana fermions in half-metal / superconductor heterostructure. https://doi.org/10.1103/physrevb.84.060510

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