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تسجيل مستخدم جديدRaman scattering due to a one-magnon excitation process in ${rm MnV_2O_4}$
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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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