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arXiv · 2412.07529

Bending-strain effects in conventional superconductors and superconducting junctions

Kjell S. Heinrich·Henning G. Hugdal·Morten Amundsen·Sol H. Jacobsen
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Abstract

We consider the effect of bending-strain in thin films of clean, conventional superconductors (S), and the proximity-induced effect of this strain in SN bilayers with a normal metal (N), and SNS junctions with equal curvatures in each superconductor. We find that the effective spin-orbit coupling due to strain in the superconductor induces both spin-polarized and unequal-spin even-frequency p-wave triplet pairings throughout the superconductor. When interfaced with a normal metal, additional odd-frequency pairings are induced, and their magnitudes can be tuned with the strain. In SNS junctions, the strain alone can induce a superconducting spin current in the junction. The spin-polarized current can undergo a $0-\pi$-transition, resulting in an in-plane, strain-induced magnetization that switches sign as a function of the strain. We discuss the underlying physics and its implications for superconducting spintronics.

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Kjell S. Heinrich, Henning G. Hugdal, Morten Amundsen, Sol H. Jacobsen. 2024-12-10. Bending-strain effects in conventional superconductors and superconducting junctions. https://doi.org/10.1038/s44306-025-00084-1

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