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arXiv · 1707.06109

Multiferroic rust: magnetoelectric effect in g\"{o}thite, $\alpha$-FeOOH

N. V. Ter-Oganessian·A. A. Guda·V. P. Sakhnenko
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Abstract

By means of symmetry analysis, density functional theory calculations, and Monte Carlo simulations we show that goethite, $\alpha$-FeOOH, is a linear magnetoelectric below its N\'{e}el temperature $T_{\rm N}=400$ K. The experimentally observed magnetic field induced spin-flop phase transition results in either change of direction of electric polarization or its suppression. Calculated value of magnetoelectric coefficient is 0.24 $\mu$C m$^{-2}$ T$^{-1}$. The abundance of goethite in nature makes it arguably the most widespread magnetoelectric material.

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N. V. Ter-Oganessian, A. A. Guda, V. P. Sakhnenko. 2017-07-19. Multiferroic rust: magnetoelectric effect in g\"{o}thite, $\alpha$-FeOOH. https://doi.org/10.1038/s41598-017-16772-w

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