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arXiv · 1412.1938

Magnetic order and electromagnon excitations in DyMnO3 studied by neutron scattering experiments

T. Finger·K. Binder·Y. Sidis·A. Maljuk·D. N. Argyriou·M. Braden
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Abstract

Magnetic order and excitations in multiferroic DyMnO3 were studied by neutron scattering experiments using a single crystal prepared with enriched 162Dy isotope. The ordering of Mn moments exhibits pronounced hysteresis arising from the interplay between Mn and Dy magnetism which possesses a strong impact on the ferroelectric polarization. The magnon dispersion resembles that reported for TbMnO3. We identify the excitations at the magnetic zone center and near the zone boundary in the b direction, which can possess electromagnon character. The lowest frequency of the zone-center magnons is in good agreement with a signal in a recent optical measurement so that this mode can be identified as the electromagnon coupled by the same Dzyaloshinski-Moriya interaction as the static multiferroic phase.

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T. Finger, K. Binder, Y. Sidis, A. Maljuk, D. N. Argyriou, M. Braden. 2014-12-05. Magnetic order and electromagnon excitations in DyMnO3 studied by neutron scattering experiments. https://doi.org/10.1103/physrevb.90.224418

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