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arXiv · 2106.04861

Einstein-de Haas Nanorotor

W. Izumida·R. Okuyama·K. Sato·T. Kato·M. Matsuo
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Abstract

We propose a nanoscale rotor embedded between two ferromagnetic electrodes that is driven by spin injection. The spin-rotation coupling allows this nanorotor to continuously receive angular momentum from an injected spin under steady current flow between ferromagnetic electrodes in an antiparallel magnetization configuration. We develop a quantum theory of this angular momentum transfer and show that a relaxation process from a precession state into a sleeping top state is crucial for the efficient driving of the nanorotor by solving the master equation. Our work clarifies a general strategy for efficient driving of a nanorotor.

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W. Izumida, R. Okuyama, K. Sato, T. Kato, M. Matsuo. 2022-01-04. Einstein-de Haas Nanorotor. https://doi.org/10.1103/physrevlett.128.017701

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