Shift current from electromagnon excitations in multiferroics

Takahiro Morimoto; Naoto Nagaosa

doi:10.1103/physrevb.100.235138

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arXiv · 1910.05182

Shift current from electromagnon excitations in multiferroics

Takahiro Morimoto·Naoto Nagaosa

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Abstract

Electromagnon is the spin wave in multiferroic materials and is known to accompany electric polarization due to the cross correlation between the charge and spin. Here, we theoretically show that the electromagnons also induce dc current upon their photoexcitations. The proposed dc current response originates from the shift current mechanism which is characterized by the so called shift vector, a geometric quantity of the Bloch wavefunctions.

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Takahiro Morimoto, Naoto Nagaosa. 2019-12-25. Shift current from electromagnon excitations in multiferroics. https://doi.org/10.1103/physrevb.100.235138

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