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arXiv · 0802.0839

The Suppression and Recovery of the Ferroelectric Phase in Multiferroic $MnWO_4$

R. P. Chaudhury·B. Lorenz·Y. Q. Wang·Y. Y. Sun·C. W. Chu
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Abstract

We report the discovery of a complete suppression of ferroelectricity in $MnWO_4$ by 10 % iron substitution and its restoration in external magnetic fields. The spontaneous polarization in $Mn_{0.9}Fe_{0.1}WO_4$ arises below 12 K in external fields above 4 T. The magnetic/ferroelectric phase diagram is constructed from the anomalies of the dielectric constant, polarization, magnetization, and heat capacity. The observations are qualitatively described by a mean field model with competing interactions and strong anisotropy. We propose that the magnetic field induces a non-collinear inversion symmetry breaking magnetic structure in $Mn_{0.9}Fe_{0.1}WO_4$.

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R. P. Chaudhury, B. Lorenz, Y. Q. Wang, Y. Y. Sun, C. W. Chu. 2008-02-06. The Suppression and Recovery of the Ferroelectric Phase in Multiferroic $MnWO_4$. https://doi.org/10.1103/physrevb.77.104406

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