在高达100 T的高磁场下,在α-RuCl3中可能存在中间量子自旋液相
Xu-Guang Zhou1, Han Li2,3, Yasuhiro H Matsuda4
1Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.
Nature communications
|September 12, 2023
概括
研究人员使用高磁场在α-RuCl中探索了量子自旋液体 (QSL) 状态. 他们在特定的场方向下发现了场诱导的QSL阶段,揭示了一个复杂的阶段图.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子材料科学 量子材料科学
- 磁力学 磁力学 是一种
背景情况:
- 量子自旋液体 (QSL) 状态是物质极受追捧的异国情调阶段.
- 基塔耶夫材料α-RuCl3是实现QSL物理学的有希望的候选物.
- 对于量子技术来说,了解磁性材料中的场诱导相对于量子技术至关重要.
研究的目的:
- 在α-RuCl3中研究场诱导量子自旋液体 (QSL) 阶段的存在和特性.
- 为了映射α-RuCl3的磁场角度相位图.
- 将实验结果与理论模型进行比较.
主要方法:
- 使用脉冲磁铁测量高场磁化高达102 T.
- 相对于晶体的c*轴,磁场方向的系统变化.
- 基于K-J-Γ模型的密度矩阵重规范化组 (DMRG) 模拟.
主要成果:
- 在35T和83T的外平面磁场下观察到两个不同的量子相位过渡,其中有一个中间的QSL相位.
- 一个在平面内的磁场在7T时诱导了一个单一的过渡,没有可观测的QSL阶段.
- 构建了一个全面的场角相位图,划分了齐克扎克,偏磁和QSL相位.
- 实验结果使用DMRG模拟以高准确度重现.
结论:
- 该研究证实了在特定磁场方向下的α-RuCl3中存在场诱导的量子自旋液体 (QSL) 阶段.
- 应用磁场的方向在确定磁相和QSL状态的出现方面起着至关重要的作用.
- 理论建模成功捕捉了实验观察到的量子相图,验证了K-J-Γ模型对α-RuCl的验证.
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