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Internal magnetic field effect on magnetoelectricity in orthorhombic $RMnO_3$ crystals

K. Noda·M. Akaki·F. Nakamura·D. Akahoshi·H. Kuwahara
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Abstract

We have investigated the role of the 4$f$ moment on the magnetoelectric (ME) effect of orthorhombic $R$MnO$_{3}$ ($R$=rare earth ions). In order to clarify the role of the 4$f$ moment, we prepared three samples: (Eu,Y)MnO$_{3}$ without the 4$f$ moment, TbMnO$_{3}$ with the anisotropic 4$f$ moment, and (Gd,Y)MnO$_{3}$ with the isotropic 4$f$ moment. The ferroelectric behaviors of these samples are different from each other in a zero magnetic field. (Eu,Y)MnO$_{3}$ and (Gd,Y)MnO$_{3}$ show the ferroelectric polarization along the a axis in the ground state, while TbMnO$_{3}$ shows it along the c axis. Such difference may arise from the influence of the anisotropic Tb$^{3+}$ 4$f$ moment. The direction of the ferroelectric polarization of $R$MnO$_{3}$ is determined by the internal magnetic field arising from the 4$f$ moment.

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K. Noda, M. Akaki, F. Nakamura, D. Akahoshi, H. Kuwahara. 2006-10-16. Internal magnetic field effect on magnetoelectricity in orthorhombic $RMnO_3$ crystals. https://doi.org/10.1016/j.jmmm.2006.10.337

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