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arXiv · 0806.1207

Electromagnons in multiferroic RMn2O5 compounds and their microscopic origin

A. B. Sushkov·M. Mostovoy·R. Valdes Aguilar·S. -W. Cheong·H. D. Drew
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Abstract

We summarize the existing experimental data on electromagnons in multiferroic RMn2O5 compounds, where R denotes a rare earth ion, Y or Bi, and discuss a realistic microscopic model of these materials based on assumption that the microscopic mechanism of magnetically-induced ferroelectricity and electromagnon absorption relies entirely on the isotropic Heisenberg exchange and magnetostrictive coupling of spins to a polar lattice mode and does not involve relativistic effects. This model explains many magnetic and optical properties of RMn2O5 manganites, such as the spin re-orientation transition, magnetically-induced polarisation, appearance of the electromagnon peak in the non-collinear spin state and the polarisation of light for which this peak is observed. We compare experimental and theoretical results on electromagnons in RMn2O5 and RMnO3 compounds.

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A. B. Sushkov, M. Mostovoy, R. Valdes Aguilar, S. -W. Cheong, H. D. Drew. 2008-06-06. Electromagnons in multiferroic RMn2O5 compounds and their microscopic origin. https://doi.org/10.1088/0953-8984%2F20%2F43%2F434210

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