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arXiv · 1201.4890

Magnetoelectricity in the system $RAl_3(BO_3)_4$ ($R$ = Tb, Ho, Er, Tm)

K. -C. Liang·R. P. Chaudhury·B. Lorenz·Y. Y. Sun·L. N. Bezmaternykh·I. A. Gudim·V. L. Temerov·C. W. Chu
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Abstract

The magnetoelectric effect in the system $RAl_3(BO_3)_4$ ($R$ = Tb, Ho, Er, Tm) is investigated between 3 K and room temperature and at magnetic fields up to 70 kOe. We show a systematic increase of the magnetoelectric effect with decreasing magnetic anisotropy of the rare earth moment. A giant magnetoelectric polarization is found in the magnetically (nearly) isotropic $HoAl_3(BO_3)_4$. The polarization value in transverse field geometry at 70 kOe reaches 3600 $\mu C/m^2$ which is significantly higher than reported values for the field-induced polarization of linear magnetoelectric or even multiferroic compounds. The results indicate a very strong coupling of the f-moments to the lattice. They further indicate the importance of the field-induced ionic displacements in the unit cell resulting in a polar distortion and a change in symmetry on a microscopic scale. The system $RAl_3(BO_3)_4$ could be interesting for the technological utilization of the high-field magnetoelectric effect.

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K. -C. Liang, R. P. Chaudhury, B. Lorenz, Y. Y. Sun, L. N. Bezmaternykh, I. A. Gudim, V. L. Temerov, C. W. Chu. 2012-01-23. Magnetoelectricity in the system $RAl_3(BO_3)_4$ ($R$ = Tb, Ho, Er, Tm). https://doi.org/10.1088/1742-6596/400/3/032046

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