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arXiv · 2110.08096

Switching of antiferromagnetic states in LiCoPO$_4$ as investigated via the magnetoelectric effect

Vilmos Kocsis·Yusuke Tokunaga·Yoshinori Tokura·Yasujiro Taguchi
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Abstract

The linear magnetoelectric (ME) effect allows for the selection or switching between two antiferromagnetic (AFM) states via the application of large electric ($E$) and magnetic ($H$) fields. Once an AFM state is selected, it is preserved by an energy barrier, even when the fields are removed. Using a simple phenomenological model, we find that this energy barrier, needed to switch the AFM state, is proportional to the product of the $E$ and $H$ coercive fields $(EH)_{\rm C}$. We measured the field and temperature dependence of $(EH)_{\rm C}$ in LiCoPO$_4$ for two different field configurations, and the data show the temperature variation of $(EH)_{\rm C}\sim(T_{\rm N}-T)^{3/2}$ in good agreement with the model. We also investigated the dynamics of the AFM domain switching using pulsed $E$-field measurements. It was found that the coercive field $(EH)_{\rm C}$ follows a power-law frequency dependence and is well described in the framework of Ishibashi-Orihara model, implying 1-dimensional character of domain wall propagation.

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Vilmos Kocsis, Yusuke Tokunaga, Yoshinori Tokura, Yasujiro Taguchi. 2021-10-15. Switching of antiferromagnetic states in LiCoPO$_4$ as investigated via the magnetoelectric effect. https://doi.org/10.1103/physrevb.104.054426

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