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arXiv · 0811.2966

Origin of electromagnon excitations in \textit{R}MnO$_3$

R. Valdés Aguilar·M. Mostovoy·A. B. Sushkov·C. L. Zhang·Y. J. Choi·S-W. Cheong·H. D. Drew
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Abstract

The origin of electromagnon excitations in cycloidal \textit{R}MnO$_3$ is explained in terms of the Heisenberg coupling between spins despite the fact that the static polarization arises from the much weaker Dzyaloshinskii-Moriya (DM) exchange interaction. We present a model that incorporates structural characteristics of this family of manganites that is confirmed by far infrared transmission data as a function of temperature and magnetic field and inelastic neutron scattering results. A deep connection is found between the magnetoelectric dynamics of the spiral phase and the static magnetoelectric coupling in the collinear E-phase of this family of manganites.

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R. Valdés Aguilar, M. Mostovoy, A. B. Sushkov, C. L. Zhang, Y. J. Choi, S-W. Cheong, H. D. Drew. 2009-01-29. Origin of electromagnon excitations in \textit{R}MnO$_3$. https://doi.org/10.1103/physrevlett.102.047203

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