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arXiv · 2401.17864

Chirality-induced Phonon-Spin Conversion at an Interface

Takumi Funato·Mamoru Matsuo·Takeo Kato
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Abstract

We consider spin injection driven by nonequilibrium chiral phonons from a chiral insulator into an adjacent metal. Phonon-spin conversion arises from the coupling of the electron spin with the microrotation associated with chiral phonons. We derive a microscopic formula for the spin injection rate at a metal-insulator interface. Our results clearly illustrate the microscopic origin of spin current generation by chiral phonons and may lead to a breakthrough in the development of spintronic devices without heavy elements.

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Takumi Funato, Mamoru Matsuo, Takeo Kato. 2024-01-31. Chirality-induced Phonon-Spin Conversion at an Interface. https://doi.org/10.1103/physrevlett.132.236201

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