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arXiv · 2108.03686

Shock-wave-like emission of spin waves induced by interfacial Dzyaloshinskii-Moriya interaction

Hong Xia·Haoran Chen·Changyeon Won·Haibin Zhao·Yizheng Wu
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Abstract

We investigated spin wave (SW) propagation and emission in thin film systems with strong interfacial Dzyaloshinskii-Moriya interaction (DMI) utilizing micromagnetic simulation. The effect of DMI on SW propagation is analogous to the flow of magnetic medium leading to the spin Doppler effect, and a spin-polarized current can enhance or suppress it. It is demonstrated that, for a Doppler velocity exceeding a critical value, a shock-wave-like emission of SWs with a cone-shape emerges from a magnetically irregular point as the cone apex. The cone angle is quantitatively determined by the DMI-induced Doppler velocity. Combining the interfacial DMI and the spin-polarized current, a constant SW emission by a static source is demonstrated, which provides a promising route to efficiently generate SWs with tunable frequency.

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Hong Xia, Haoran Chen, Changyeon Won, Haibin Zhao, Yizheng Wu. 2021-08-08. Shock-wave-like emission of spin waves induced by interfacial Dzyaloshinskii-Moriya interaction. https://doi.org/10.1016/j.jmmm.2022.169264

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