在中心对称的Gd_{2}PdSi_{3}中,无同位的Skyrmion和多q旋转动力学
M Gomilšek1,2,3, T J Hicken3,4, M N Wilson3,5
1Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, Slovenia.
Physical review letters
|February 14, 2025
概括
这项研究揭示了旋转异构性稳定了中心对称材料中的 skyrmion 格子. 子光谱学揭示了Gd_{2}PdSi_{3}中的异型自旋动力学,表明其基本状态中具有类似于子的结构.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
背景情况:
- 斯基米子是拓性的磁性准粒子,通常通过Dzyaloshinskii-Moriya相互作用 (DMI) 在非中心对称材料中稳定.
- 像Gd和Eu基化合物这样的中心对称材料为斯基米安稳定提供了一个替代的,没有DMI的环境,但它们的机制和磁性基态仍在争论中.
- 了解这些无DMI系统对于推进基于skyrmion的技术至关重要.
研究的目的:
- 研究中心对称的斯基米子网格 (SL) 主体Gd_{2}PdSi_{3}的静态和动态旋转特性.
- 澄清SL阶段的稳定机制以及DMI无材料中的磁性基态的性质.
- 确定旋转异构性在稳定磁相中的作用.
主要方法:
- 子光谱学 (muSR) 用于探测静态和动态自旋特性.
- 分析的重点是Gd_{2}PdSi_{3}的不同磁相间的旋转波动和动态.
- 子光谱允许在原子尺度上灵敏地检测磁性秩序和动态.
主要成果:
- 在非平面SL阶段观察到高度异构的旋转波动,突出显示了旋转异构的重要作用.
- 在基态不相称的磁相 (IC-1) 中检测到强烈的异构旋转动力学,这表明了类似于maroon的多q结构.
- 较高场,共平面不相称的磁相 (IC-2) 呈现出几乎同otropic 旋转动态,与单 q 结构一致.
结论:
- 旋转异构性是稳定中心对称材料中斯基米子-晶格相的一个关键因素.
- Gd_{2}PdSi_{3}的基态磁相可能具有复杂的maroon-like多q结构.
- 子光谱学为外来磁性材料复杂的自旋动力学和磁性结构提供了宝贵的见解.
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