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arXiv · 2505.23083

Theory of spin Seebeck effect activated by acoustic chiral phonons

Naoki Nishimura·Takumi Funato·Mamoru Matsuo·Takeo Kato
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Abstract

We theoretically explore the generation of spin current driven by a temperature gradient in a junction between a chiral insulator and a normal metal. Based on the gyromagnetic response induced by microscopic acoustic-phonon-mediated lattice rotation, we derive a formula for the spin current when a finite temperature difference is imposed between two ends of the sample. We clarify how the phonon-mediated spin current depends on the sample geometry, the thermal conductivity, the heat conductance at the interface, and the average temperature. Our formulation provides a microscopic foundation for the chiral-phonon-activated spin Seebeck effect without relying on magnetism or spin-orbit interactions.

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Naoki Nishimura, Takumi Funato, Mamoru Matsuo, Takeo Kato. 2025-05-29. Theory of spin Seebeck effect activated by acoustic chiral phonons. https://doi.org/10.1016/j.jmmm.2025.173386

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