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Electromagnons in multiferroic YMn2O5 and TbMn2O5

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

Based on temperature dependent far infrared transmission spectra of YMn2O5 and TbMn2O5 single crystals, we report the observation of electric dipole-active magnetic excitations, or electromagnons, in these multiferroics. Electromagnons are found to be directly responsible for the step-like anomaly of the static dielectric constant at the commensurate--incommensurate magnetic transition and are the origin of the colossal magneto-dielectric effect reported in these multiferroics.

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A. B. Sushkov, R. Valdes Aguilar, S. Park, S-W. Cheong, H. D. Drew. 2006-09-22. Electromagnons in multiferroic YMn2O5 and TbMn2O5. https://doi.org/10.1103/physrevlett.98.027202

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