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arXiv · 1109.3090

Prediction of the Magnetotoroidic Effect from Atomistic Simulations

Wei Ren·L. Bellaiche
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Abstract

An effective Hamiltonian technique is used to investigate the effect of applying curled electric fields on physical properties of stress-free BiFeO3 dots being under open-circuit electrical boundary conditions. It is discovered that such fields can lead to a control of not only the magnitude but also the direction of the magnetization. On a microscopic point of view, such control originates from the field-induced transformation or switching of electrical vortices and their couplings with oxygen octahedral tilts and magnetic dipoles. This control involves striking intermediate states, and constitutes a novel phenomenon that can be termed as "magnetotoroidic" effect.

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Wei Ren, L. Bellaiche. 2011-09-14. Prediction of the Magnetotoroidic Effect from Atomistic Simulations. https://doi.org/10.1103/physrevlett.107.127202

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