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DOE OSTI · 1904638

Angularly quantized spin rotations in hexagonal LuMnO 3

Kim, Seung·Nam, Jiyeon·Xu, Xianghan·Cheong, Sang-Wook·Yang, In-Sang
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Abstract

Optical control of the spin degree of freedom is often desired in application of the spin technology. Here we report spin-rotational excitations observed through inelastic light scattering of the hexagonal LuMnO 3 in the antiferromagnetically (AFM) ordered state. We propose a model based on the spin–spin interaction Hamiltonian associated with the spin rotation of the Mn ions, and find that the spin rotations are angularly quantized by 60°, 120°, and 180°. Angular quantization is considered to be a consequence of the symmetry of the triangular lattice of the Mn-ion plane in the hexagonal LuMnO 3 . These angularly-quantized spin excitations may be pictured as isolated flat bubbles in the sea of the ground state, which may lead to high-density information storage if applied to spin devices. Optically pumped and detected spin-excitation bubbles would bring about the advanced technology of optical control of the spin degree of freedom in multiferroic materials.

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Kim, Seung, Nam, Jiyeon, Xu, Xianghan, Cheong, Sang-Wook, Yang, In-Sang. 2022-02-14. Angularly quantized spin rotations in hexagonal LuMnO 3. https://doi.org/10.1038/s41598-022-06394-2

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