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arXiv · 2106.03332

Voltage-control of damping constant in magnetic-insulator/topological-insulator bilayers

Takahiro Chiba·Alejandro O. Leon·Takashi Komine
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Abstract

The magnetic damping constant is a critical parameter for magnetization dynamics and the efficiency of memory devices and magnon transport. Therefore, its manipulation by electric fields is crucial in spintronics. Here, we theoretically demonstrate the voltage-control of magnetic damping in ferro- and ferrimagnetic-insulator (FI)/topological-insulator (TI) bilayers. Assuming a capacitor-like setup, we formulate an effective dissipation torque induced by spin-charge pumping at the FI/TI interface as a function of an applied voltage. By using realistic material parameters, we find that the effective damping for a FI with 10nm thickness can be tuned by one order of magnitude under the voltage with 0.25V. Also, we provide perspectives on the voltage-induced modulation of the magnon spin transport on proximity-coupled FIs.

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Takahiro Chiba, Alejandro O. Leon, Takashi Komine. 2021-06-07. Voltage-control of damping constant in magnetic-insulator/topological-insulator bilayers. https://doi.org/10.1063/5.0046217

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