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arXiv · 2111.06765

Simple microscopic model for magneto-electric coupling in type-II antiferromagnetic multiferroics

L. Pili·R. A. Borzi·D. C. Cabra·S. A. Grigera
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Abstract

We present a simple two-dimensional model in which the lattice degrees of freedom mediate the interactions between magnetic moments and electric dipoles. This model reproduces basic features, such as a sudden electric polarization switch-off when a magnetic field is applied and the ubiquitous dimerized distortion patterns and magnetic $\uparrow \uparrow \downarrow \downarrow$ ordering, observed in several multiferroic materials of different composition. The list includes E-type manganites, RMnO$_3$, nickelates such as in YNiO$_3$ and other materials under strain, such as TbMnO$_3$. In spite of its simplicity, the model presented here captures the essence of the origin of multiferroicity in a large class of type II multiferroics.

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L. Pili, R. A. Borzi, D. C. Cabra, S. A. Grigera. 2021-11-12. Simple microscopic model for magneto-electric coupling in type-II antiferromagnetic multiferroics. https://doi.org/10.1103/physrevb.105.094428

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