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arXiv · 1008.5354

Magnetic excitations in the low-temperature ferroelectric phase of multiferroic YMn2O5 using inelastic neutron scattering

J. -H. Kim·M. A. van. der. Vegte·A. Scaramucci·S. Artyukhin·J. -H. Chung·S. Park·S. -W. Cheong·M. Mostovoy·S. -H. Lee
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Abstract

We studied magnetic excitations in a low-temperature ferroelectric phase of the multiferroic YMn2O5 using inelastic neutron scattering (INS). We identify low-energy magnon modes and establish a correspondence between the magnon peaks observed by INS and electromagnon peaks observed in optical absorption [1]. Furthermore, we explain the microscopic mechanism, which results in the lowest-energy electromagnon peak, by comparing the inelastic neutron spectral weight with the polarization in the commensurate ferroelectric phase.

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J. -H. Kim, M. A. van. der. Vegte, A. Scaramucci, S. Artyukhin, J. -H. Chung, S. Park, S. -W. Cheong, M. Mostovoy, S. -H. Lee. 2011-07-01. Magnetic excitations in the low-temperature ferroelectric phase of multiferroic YMn2O5 using inelastic neutron scattering. https://doi.org/10.1103/physrevlett.107.097401

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