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arXiv · 1704.04303

Spin pumping into superconductors: A new probe of spin dynamics in a superconducting thin film

Masashi Inoue·Masanori Ichioka·Hiroto Adachi
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Abstract

Spin pumping refers to the microwave-driven spin current injection from a ferromagnet into the adjacent target material. We theoretically investigate the spin pumping into superconductors by fully taking account of impurity spin-orbit scattering that is indispensable to describe diffusive spin transport with finite spin diffusion length. We calculate temperature dependence of the spin pumping signal and show that a pronounced coherence peak appears immediately below the superconducting transition temperature Tc, which survives even in the presence of the spin-orbit scattering. The phenomenon provides us with a new way of studying the dynamic spin susceptibility in a superconducting thin film. This is contrasted with the nuclear magnetic resonance technique used to study a bulk superconductor.

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Masashi Inoue, Masanori Ichioka, Hiroto Adachi. 2017-07-14. Spin pumping into superconductors: A new probe of spin dynamics in a superconducting thin film. https://doi.org/10.1103/physrevb.96.024414

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