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arXiv · 1112.5822

Topological superconductivity in bilayer Rashba system

Sho Nakosai·Yukio Tanaka·Naoto Nagaosa
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Abstract

We theoretically study a possible topological superconductivity in the interacting two layers of Rashba systems, which can be fabricated by the hetero-structures of semiconductors and oxides. The hybridization, which induces the gap in the single particle dispersion, and the electron-electron interaction between the two layers leads to the novel phase diagram of the superconductivity. It is found that the topological superconductivity {\it without breaking time-reversal symmetry} is realized when (i) the Fermi energy is within the hybridization gap, and (ii) the inter-layer interaction is repulsive, both of which can be satisfied in realistic systems. Edge channels are studied in a tight-binding model numerically, and the several predictions on experiments are also given.

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Sho Nakosai, Yukio Tanaka, Naoto Nagaosa. 2011-12-26. Topological superconductivity in bilayer Rashba system. https://doi.org/10.1103/physrevlett.108.147003

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