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arXiv · 1012.4073

Raman scattering due to a one-magnon excitation process in ${\rm MnV_2O_4}$

S. Miyahara·K. Takubo·T. Suzuki·T. Katsufuji·N. Furukawa
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Abstract

Unconventional peak structure in the Raman spectra due to magnon excitation at low temperature is observed in spinel magnet ${\rm MnV_2O_4}$, where a noncollinear spin state is realized by geometrical frustration. We propose a new mechanism to induce such a Raman scattering process due to a one-magnon excitation of the noncollinear spin state. Novel features of the scattering such as selection rules and peak position observed experimentally in ${\rm MnV_2O_4}$ can be explained quite naturally by considering the present one-magnon process. We also discuss that such one-magnon process may exist in various materials with noncollinear spin structures.

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S. Miyahara, K. Takubo, T. Suzuki, T. Katsufuji, N. Furukawa. 2010-12-18. Raman scattering due to a one-magnon excitation process in ${\rm MnV_2O_4}$. https://arxiv.org/abs/1012.4073

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