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arXiv · 1104.1232

Stability of Unconventional Superconductivity on Surfaces of Topological Insulators

Yuto Ito·Youhei Yamaji·Masatoshi Imada
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Abstract

Superconductivity on the surface of topological insulators is known to be anisotropic and unconventional in that the symmetry is the mixture of s-wave and nodeless p-wave component. In contrast to Anderson's theorem for the insensitivity of the s-wave superconducting critical temperature to the nonmagnetic (time-reversal symmetric (TRS)) impurities, anisotropic superconductors including nodeless p-wave one are in general fragile even with small concentration of the TRS impurities. By employing the Abrikosov-Gor'kov theory, we clarify that this type of unconventional superconductivity emergent on the surface state of the strong topological insulators robustly survive against TRS impurities.

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Yuto Ito, Youhei Yamaji, Masatoshi Imada. 2011-04-07. Stability of Unconventional Superconductivity on Surfaces of Topological Insulators. https://doi.org/10.1143/jpsj.80.063704

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