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  • Open Access

Magnetic field direction dependence of the spin liquid state in α−RuCl3

Hua Xu, Zidong Wang, Boshi Mu, and Yan Liu*

  • *Contact author: liuyanphys@mail.neu.edu.cn
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Phys. Rev. Research 7, 043237 – Published 1 December, 2025

DOI: https://doi.org/10.1103/wnrc-cjkn

Abstract

Numerous experiments have shown that α−RuCl3 exhibits a spin liquid (SL) state near 7.1 T when an in-plane magnetic field is applied perpendicular to the Ru-Ru bond directions ([110]), while SL states are rarely observed under fields applied along the Ru-Ru bond ([100]). The underlying mechanism for this pronounced anisotropy remains elusive. In this work, we employ semiclassical spin dynamics simulations to investigate the magnetization evolution of α−RuCl3 with lattice distortion under varying external magnetic fields. It is found that each [100] direction has its own dominant orientation, and each [110] orientation marks the boundary, where the two alignments compete with each other. The magnetizations are influenced by multiple interactions and perturbations from lattice distortions, leading to the occurrence of the SL state in the [110] direction. These results provide new insights into the field-induced phase transitions in α−RuCl3 and the microscopic mechanisms underlying the emergence of spin liquid behavior.

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Phys. Rev. Research 7, 043237– Published 1 December, 2025
  • Received 7 July 2025
  • Accepted 20 October 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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