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arXiv · 2311.04000

Structural Transition and Magnetic Anisotropy in $\alpha$-RuCl$_{3}$

Subin Kim·Ezekiel Horsley·Jacob P. C. Ruff·Beatriz D. Moreno·Young-June Kim
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Abstract

We report X-ray diffraction and magnetic susceptibility studies of the structural phase transition in $\alpha$-RuCl$_{3}$. By utilizing a single crystal sample with predominantly single twin domain, we show that $\alpha$-RuCl$_{3}$ goes from high-temperature C2/m structure to a rhombohedral structure with R$\bar{3}$ symmetry at low temperature. While the defining feature of the structural transition is changing the stacking direction from the monoclinic a-axis to the b-axis, bond-anisotropy disappears when the structural change occurs, indicating that the local $C_3$ symmetry is restored within the honeycomb layer. The symmetry change is corroborated by the vanishing magnetic anisotropy in the low-temperature structure. Our study demonstrates that magnetic interaction is extremely sensitive to structural details in $\alpha$-RuCl$_{3}$, which could explain the sample dependence found in this material.

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Subin Kim, Ezekiel Horsley, Jacob P. C. Ruff, Beatriz D. Moreno, Young-June Kim. 2023-11-07. Structural Transition and Magnetic Anisotropy in $\alpha$-RuCl$_{3}$. https://arxiv.org/abs/2311.04000

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