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arXiv · 1302.1099

Bulk magnetoelectricity in the hexagonal manganites and ferrites

Hena Das·Aleksander L. Wysocki·Yanan Geng·Weida Wu·Craig J. Fennie
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Abstract

Improper ferroelectricity (trimerization) in the hexagonal manganites RMnO$_3$ leads to a network of coupled structural and magnetic vortices that induce domain wall magnetoelectricity and magnetization neither of which, however, occurs in the bulk. Here we combined first-principles calculations, group-theoretic techniques, and microscopic spin models to show how the trimerization not only induces a polarization but also a bulk magnetization and bulk magnetoelectric (ME) effect. This results in the existence of a bulk linear ME vortex structure or a bulk ME coupling such that if direction of polarization reverses so does magnetization. To measure the predicted ME vortex, we suggest RMnO$_3$ under large magnetic field. We suggest a family of materials, the hexagonal RFeO$_3$ ferrites, also display the predicted phenomena in their ground state.

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Hena Das, Aleksander L. Wysocki, Yanan Geng, Weida Wu, Craig J. Fennie. 2013-02-05. Bulk magnetoelectricity in the hexagonal manganites and ferrites. https://doi.org/10.1038/ncomms3998

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