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arXiv · 1107.4404

Interface induced giant magnetoelectric coupling in multiferroic superlattices

Hongwei Wang·Lixin He·Xifan Wu
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Abstract

The electric and magnetic properties of (BaTiO$_3$)$_n$/(CaMnO$_3$)$_n$ short-period superlattices are studied by the first-principles calculations. The local electric polarizations in the CaMnO$_3$ layers are significant, comparable to that in the BaTiO$_3$ layers. Remarkably, the electric polarization is almost doubled when the spin configuration changes from antiferromagnetic to ferromagnetic in the superlattices, indicating a giant magnetoelectric coupling. This enhancement of the magnetoelectric coupling is due to the suppression of the antiferrodistortive mode in the CaMnO$_3$ layers at the interfaces.

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Hongwei Wang, Lixin He, Xifan Wu. 2011-07-22. Interface induced giant magnetoelectric coupling in multiferroic superlattices. https://doi.org/10.1209/0295-5075%2F100%2F17005

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