Novel optical properties of spin-wave excitations in non-centrosymmetric oxides: the case of Ba2CoGe2O7
We have recently demonstrated that multiferroics host exotic optical phenomena, such as non-reciprocal directional dichroism  and natural optical activity , for spin-wave excitations owing to the strong dynamic magnetoelectric coupling. The observed large optical anisotropies can pave the way for novel THz applications e.g. unidirectional waveguides or polarization rotators.
KeywordsChiral Phase Ferroelectric Polarization Natural Optical Activity Magnon Mode Molecular Light Scattering
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This work was supported by the Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST Program), Japan.
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