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arXiv · 1909.01345

Controlling the Superconducting Transition by Rotation of an Inversion Symmetry-Breaking Axis

Abstract

We consider a hybrid structure where a material with Rashba-like spin-orbit coupling is proximity coupled to a conventional superconductor. We find that the superconducting critical temperature $T_c$ can be tuned by rotating the vector $\boldsymbol{n}$ characterizing the axis of broken inversion symmetry. This is explained by a leakage of $s$-wave singlet Cooper pairs out of the superconducting region, and by conversion of $s$-wave singlets into other types of correlations, among these $s$-wave odd-frequency pairs robust to impurity scattering. These results demonstrate a conceptually different way of tuning $T_c$ compared to the previously studied variation of $T_c$ in magnetic hybrids.

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Lina G. Johnsen, Kristian Svalland, Jacob Linder. 2019-09-03. Controlling the Superconducting Transition by Rotation of an Inversion Symmetry-Breaking Axis. https://doi.org/10.1103/physrevlett.125.107002

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