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arXiv · 0806.0835

Pressure-induced polarization reversal in multiferroic $YMn_2O_5$

Rajit P. Chaudhury·Clarina R. dela Cruz·Bernd Lorenz·Yanyi Sun·Ching-Wu Chu·S. Park·Sang-W. Cheong
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Abstract

The low-temperature ferroelectric polarization of multiferroic $YMn_2O_5$ is completely reversed at a critical pressure of 10 kbar and the phase transition from the incommensurate to the commensurate magnetic phase is induced by pressures above 14 kbar. The high-pressure data correlate with thermal expansion measurements indicating a significant lattice strain at the low-temperature transition into the incommensurate phase. The results support the exchange striction model for the ferroelectricity in multiferroic $RMn_2O_5$ compounds and they show the importance of magnetic frustration as well as the spin-lattice coupling.

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Rajit P. Chaudhury, Clarina R. dela Cruz, Bernd Lorenz, Yanyi Sun, Ching-Wu Chu, S. Park, Sang-W. Cheong. 2008-06-04. Pressure-induced polarization reversal in multiferroic $YMn_2O_5$. https://doi.org/10.1103/physrevb.77.220104

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