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arXiv · 1208.4315

Odd-frequency superconducting pairing in topological insulators

Annica M. Black-Schaffer·Alexander V. Balatsky
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Abstract

We discuss the appearance of odd-frequency spin-triplet s-wave superconductivity, first proposed by Berezinskii [{\it JETP} {\bf 20}, 287 (1974)], on the surface of a topological insulator proximity coupled to a conventional spin-singlet s-wave superconductor. Using both analytical and numerical methods we show that this disorder robust odd-frequency state is present whenever there is an in-surface gradient in the proximity induced gap, including superconductor-normal state (SN) junctions. The time-independent order parameter for the odd-frequency superconductor is proportional to the in-surface gap gradient. The induced odd-frequency component does not produce any low-energy states.

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Annica M. Black-Schaffer, Alexander V. Balatsky. 2012-08-21. Odd-frequency superconducting pairing in topological insulators. https://doi.org/10.1103/physrevb.86.144506

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