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arXiv · 2309.10583

Multiple Magnetoelectric Plateaux in Polar Magnet Fe$_2$Mo$_3$O$_8$

Qian Chen·Atsushi Miyake·Takashi Kurumaji·Keisuke Matsuura·Fumitaka Kagawa·Shin Miyahara·Yoshinori Tokura·Masashi Tokunaga
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Abstract

The magnetization and electric polarization of a polar antiferromagnet Fe$_2$Mo$_3$O$_8$ are studied up to 66 T for spin-saturation magnetic fields applied along the polar axis. The magnetization process at 1.4 K exhibited multistep structures below the saturation field of 65 T. The electric polarization along the polar axis exhibits a similar multistep behavior with a total change of 1.2 $\rm{\mu}C/cm^{2}$. A combined triangular-lattice antiferromagnetic model with strong Ising-type spin anisotropy reproduces this multistep magnetoelectric (ME) effect. The exchange striction mechanism explains the remarkable ME response in the two sub-lattice type-I multiferroic materials. These results and interpretation demonstrate a method for realizing multistage magnetoelectric effects in hybrid spin systems.

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Qian Chen, Atsushi Miyake, Takashi Kurumaji, Keisuke Matsuura, Fumitaka Kagawa, Shin Miyahara, Yoshinori Tokura, Masashi Tokunaga. 2023-09-19. Multiple Magnetoelectric Plateaux in Polar Magnet Fe$_2$Mo$_3$O$_8$. https://arxiv.org/abs/2309.10583

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