Electrical control of superconducting spin valves using ferromagnetic helices

Tancredi Salamone; Henning G. Hugdal; Morten Amundsen; Sol H. Jacobsen

doi:10.1063/5.0210691

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arXiv · 2404.05798

Electrical control of superconducting spin valves using ferromagnetic helices

Tancredi Salamone·Henning G. Hugdal·Morten Amundsen·Sol H. Jacobsen

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Abstract

The geometrical properties of a helical ferromagnet are shown theoretically to control the critical temperature of a proximity-coupled superconductor. Using the Usadel equation for diffusive spin transport, we provide self-consistent analysis of how curvature and torsion modulate the proximity effect. When the helix is attached to a piezoelectric actuator, the pitch of the helix -- and hence the superconducting transition -- can be controlled electrically.

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Tancredi Salamone, Henning G. Hugdal, Morten Amundsen, Sol H. Jacobsen. 2024-04-08. Electrical control of superconducting spin valves using ferromagnetic helices. https://doi.org/10.1063/5.0210691

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