AI 中文总结
研究通过第一性原理计算构建有效赝自旋模型，探究卤化物对Ru$X_3$磁竞争的调控，发现RuBr$_3$万尼尔轨道更扩展、层间交换作用更强，轨道依赖库仑各向异性减小能量差，阐明了卤化物取代控制磁竞争的机制。
AI 中文摘要
自旋轨道莫特绝缘体Ru$X_3$（$X =$ Cl, Br）作为实现Kitaev自旋液体的候选材料备受关注。本研究通过第一性原理计算得到的多轨道哈伯德模型构建有效赝自旋模型，研究RuCl$_3$和RuBr$_3$的磁态。发现RuBr$_3$的万尼尔轨道更扩展，层间交换相互作用更强，增强了三维相关性。轨道依赖的库仑各向异性进一步减小铁磁和锯齿状态的能量差。结果阐明了卤化物取代如何通过层间交换相互作用和轨道依赖库仑相互作用的影响来控制Ru$X_3$中的磁竞争。
英文摘要
The spin-orbital Mott insulators Ru$X_3$ ($X =$ Cl, Br) have attracted considerable attention as promising candidate materials for realizing a Kitaev spin liquid. In this study, we construct effective pseudospin models from multiorbital Hubbard models derived from first-principles calculations and investigate the magnetic states of RuCl$_3$ and RuBr$_3$. From the constructed effective models, we find that RuBr$_3$ has more extended Wannier orbitals and stronger interlayer exchange interactions than RuCl$_3$. These interactions enhance three-dimensional correlations, consistent with the stronger antiferromagnetic tendency experimentally inferred for RuBr$_3$. Orbital-dependent Coulomb anisotropy further reduces the energy difference between ferromagnetic and zigzag states. Our results clarify how halogen substitution controls magnetic competition in Ru$X_3$ through interlayer exchange interactions and effects of orbital-dependent Coulomb interactions.
Comments17 pages, 11 figures
