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arXiv · 1801.07943

Spin-current coherence peak in superconductor/magnet junctions

Maki Umeda·Yuki Shiomi·Takashi Kikkawa·Tomohiko Niizeki·Jana Lustikova·Saburo Takahashi·Eiji Saitoh
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Abstract

Coherence peak effects in a superconductor induced by a thermal spin current are reported. We measured inverse spin Hall effects induced by spin injection from a ferrimagnetic insulator Y$_3$Fe$_5$O$_{12}$ into a superconductor NbN using longitudinal spin Seebeck effects. In the vicinity of the superconducting transition temperature of the NbN, a large enhancement of the spin Seebeck voltage is observed, whose sign is opposite to that for the vortex Nernst effect, but is consistent with a calculation for a coherence peak effect in the superconductor NbN.

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Maki Umeda, Yuki Shiomi, Takashi Kikkawa, Tomohiko Niizeki, Jana Lustikova, Saburo Takahashi, Eiji Saitoh. 2018-01-24. Spin-current coherence peak in superconductor/magnet junctions. https://doi.org/10.1063/1.5027456

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