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arXiv · 1705.03349

Unidirectional control of optically induced spin waves

Isao Yoshimine·Yoshito Y. Tanaka·Tsutomu Shimura·Takuya Satoh
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Abstract

Unidirectional control of optically induced spin waves in a rare-earth iron garnet crystal is demonstrated. We observed the interference of two spin-wave packets with different initial phases generated by circularly polarized light pulses. This interference results in unidirectional propagation if the spin-wave sources are spaced apart at 1/4 of the wavelength of the spin waves and the initial phase difference is set to pi/2. The propagating direction of the spin wave is switched by the polarization helicity of the light pulses. Moreover, in a numerical simulation, applying more than two spin-wave sources with a suitable polarization and spot shape, arbitrary manipulation of the spin wave by the phased array method was replicated.

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Isao Yoshimine, Yoshito Y. Tanaka, Tsutomu Shimura, Takuya Satoh. 2017-05-09. Unidirectional control of optically induced spin waves. https://doi.org/10.1209/0295-5075/117/67001

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