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arXiv · 1302.1252

Unified Model of Ferroelectricity Induced by Spin Order

H. J. Xiang·P. S. Wang·M. -H. Whangbo·X. G. Gong
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Abstract

The ferroelectricity of multiferroics induced by spin order is commonly explained by considering either purely electronic or ion-displacement contribution. However, there is no general model which includes both effects simultaneously. Here, we suggest a realistic model to describe the ion-displacement part of the ferroelectricity based on the spin-lattice coupling Hamiltonian. Combining this model with our previous pure electronic model for spin-order induced polarization, we propose a unified model that includes both effects. By applying the unified model to representative multiferroics where the electronic and ion-displacement contributions vary widely, we find that this model can not only reproduce the first-principles results, but also provide insight into the origin of ferroelectricity.

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H. J. Xiang, P. S. Wang, M. -H. Whangbo, X. G. Gong. 2013-02-06. Unified Model of Ferroelectricity Induced by Spin Order. https://doi.org/10.1103/physrevb.88.054404

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