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arXiv · 2605.09729

Magnetic structure in the two-dimensional van der Waals ferromagnet Fe$_3$GaTe$_2$

Po-Chun Chang·Sabreen Hammouda·Yung-Hsiang Tung·Yishui Zhou·Iurii Kibalin·Bachir Ouladdiaf·Chao-Hung Du·Yixi Su
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Abstract

High-quality single crystals of the two-dimensional van der Waals ferromagnet Fe$_3$GaTe$_2$ (FGaT) were successfully grown using the chemical vapour transport method, which effectively reduced surface impurities compared with conventional self-flux growth. Structural and magnetic characterizations were performed using single-crystal X-ray and neutron diffraction. The results confirm that FGaT crystallizes in the hexagonal $P6_3/mmc$ structure, with Fe occupying two inequivalent sites (Fe$^{i}$ and Fe$^{ii}$), where the magnetic moment of Fe$^{i}$ [1.9(2) $\mu_B$] is larger than that of Fe$^{ii}$ [1.4(6) $\mu_B$]. The magnetic easy axis is oriented along the $c$ axis and the Curie temperature ($T_C$) is approximately 355-360 K. Compared with Fe$_3$GeTe$_2$ (FGT), FGaT exhibits a slightly expanded $a$ axis and a contracted $c$ axis, resulting in a reduction in the Fe$^{i}$-Fe$^{ii}$ interatomic distance along the $c$ axis. This pronounced contraction could strengthen the Fe$-$Fe exchange interaction, which is believed to be the key factor responsible for the significantly higher $T_C$ in FGaT relative to FGT.

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Po-Chun Chang, Sabreen Hammouda, Yung-Hsiang Tung, Yishui Zhou, Iurii Kibalin, Bachir Ouladdiaf, Chao-Hung Du, Yixi Su. 2026-05-10. Magnetic structure in the two-dimensional van der Waals ferromagnet Fe$_3$GaTe$_2$. https://doi.org/10.1107/s160057672600230x

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