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Structural Anomalies at the Magnetic and Ferroelectric Transitions in $RMn_2O_5$ (R=Tb, Dy, Ho)

C. R. dela Cruz·F. Yen·B. Lorenz·M. M. Gospodinov·C. W. Chu·W. Ratcliff·J. W. Lynn·S. Park·S-W. Cheong
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Abstract

Strong anomalies of the thermal expansion coefficients at the magnetic and ferroelectric transitions have been detected in multiferroic $RMn_2O_5$. Their correlation with anomalies of the specific heat and the dielectric constant is discussed. The results provide evidence for the magnetic origin of the ferroelectricity mediated by strong spin-lattice coupling in the compounds. Neutron scattering data for $HoMn_2O_5$ indicate a spin reorientation at the two low-temperature phase transitions.

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C. R. dela Cruz, F. Yen, B. Lorenz, M. M. Gospodinov, C. W. Chu, W. Ratcliff, J. W. Lynn, S. Park, S-W. Cheong. 2006-03-01. Structural Anomalies at the Magnetic and Ferroelectric Transitions in $RMn_2O_5$ (R=Tb, Dy, Ho). https://doi.org/10.1103/physrevb.73.100406

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