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arXiv · 0705.4675

Thermal expansion and pressure effect in MnWO4

R. P. Chaudhury·F. Yen·C. R. dela Cruz·B. Lorenz·Y. Q. Wang·Y. Y. Sun·C. W. Chu
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Abstract

MnWO4 has attracted attention because of its ferroelectric property induced by frustrated helical spin order. Strong spin-lattice interaction is necessary to explain ferroelectricity associated with this type of magnetic order.We have conducted thermal expansion measurements along the a, b, c axes revealing the existence of strong anisotropic lattice anomalies at T1=7.8 K, the temperature of the magnetic lock-in transition into a commensurate low-temperature (reentrant paraelectric) phase. The effect of hydrostatic pressure up to 1.8 GPa on the FE phase is investigated by measuring the dielectric constant and the FE polarization. The low- temperature commensurate and paraelectric phase is stabilized and the stability range of the ferroelectric phase is diminished under pressure.

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R. P. Chaudhury, F. Yen, C. R. dela Cruz, B. Lorenz, Y. Q. Wang, Y. Y. Sun, C. W. Chu. 2007-05-31. Thermal expansion and pressure effect in MnWO4. https://doi.org/10.1016/j.physb.2007.10.327

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