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arXiv · 2504.05139

Violation of local reciprocity in charge-orbital interconversion

Hisanobu Kashiki·Hiroki Hayashi·Dongwook Go·Yuriy Mokrousov·Kazuya Ando
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Abstract

We demonstrate a violation of local reciprocity in the interconversion between charge and orbital currents. By investigating orbital torque and orbital pumping in W/Ni bilayers, we show that the charge-orbital interconversion in the bulk of the W layer exhibits opposite signs in the direct and inverse processes -- the direct and inverse orbital Hall effects being positive and negative, respectively. This finding provides direct evidence of local nonreciprocity in the charge-orbital interconversion, in agreement with a theoretical prediction. These results highlight the unique characteristics of charge-orbital coupled transport and offer fundamental insights into the mechanisms underlying orbital-current-driven phenomena.

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Hisanobu Kashiki, Hiroki Hayashi, Dongwook Go, Yuriy Mokrousov, Kazuya Ando. 2025-04-07. Violation of local reciprocity in charge-orbital interconversion. https://doi.org/10.1103/nns5-cn81

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