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arXiv · 1505.07183

Proximity-free enhancement of anomalous Nernst effects in metallic multilayers

Ken-ichi Uchida·Takashi Kikkawa·Takeshi Seki·Takafumi Oyake·Junichiro Shiomi·Koki Takanashi·Eiji Saitoh
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Abstract

The anomalous Nernst effect (ANE) has been investigated in alternately-stacked multilayer films comprising paramagnetic and ferromagnetic metals. We found that the ANE is enhanced with increasing the number of the paramagnet/ferromagnet interfaces with keeping the total thickness of the films constant, and that the enhancement appears even in the absence of magnetic proximity effects; similar behavior was observed not only in Pt/Fe multilayers but also in Au/Fe and Cu/Fe multilayers free from proximity ferromagnetism. This universal enhancement of the ANE in the metallic multilayers suggests the presence of unconventional interface-induced thermoelectric conversion in the Fe films attached to the paramagnets.

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Ken-ichi Uchida, Takashi Kikkawa, Takeshi Seki, Takafumi Oyake, Junichiro Shiomi, Koki Takanashi, Eiji Saitoh. 2015-05-27. Proximity-free enhancement of anomalous Nernst effects in metallic multilayers. https://doi.org/10.1103/physrevb.92.094414

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