在单个 Dy adatom 铁磁磁体中垂直的磁性异构性
Alexander B Shick1, Frantisek Maca2, Itzhak Halevy3
1FZU-Institute of Physics, Czech Academy of Science, Na Slovance 2, 18221, Prague, Czech Republic. shick@fzu.cz.
Scientific reports
|October 17, 2025
概括
这项研究研究了铁磁石烯/Ni{111}基板上的Dy原子,揭示了独特的磁时刻和重要的磁异性质能量 (MAE),这对于高密度记录至关重要. 这些发现改进了密度函数理论 (DFT+U) 对稀土纳米结构的应用.
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
- 量子化学 是一个量子化学.
背景情况:
- 了解表面单个原子的电子结构和磁性是开发先进磁性材料的关键.
- 铁磁基板,如Ni{11},为研究表面磁性提供了独特的平台.
- 石墨烯层可以改变吸附原子的磁性.
研究的目的:
- 为了研究在铁磁石烯/Ni{111}基板上被吸附的单个 (Dy) 原子的电子结构和磁性.
- 计算磁矩,磁性异构能量 (MAE),并将理论结果与实验可能性进行比较.
- 为了解决常规密度函数理论 (DFT+U) 中的模两可的问题,对稀土土质的应用.
主要方法:
- 密度函数理论与哈伯德-I近似与安德森杂质模型 (DFT+U(HIA)).
- 计算Dy f-shell的旋转,轨道和总磁矩.
- 计算X射线吸收 (XAS) 和磁圆二极化 (XMCD) 频谱.
- 从地面状态能量差异中确定磁性异构性能量 (MAE).
主要成果:
- 在特定配置中的双价Dy adatom被确定具有显著的旋转,轨道和总磁矩.
- Dy f-shell 的磁矩偏离了原子秒的Hund 规则.
- 铁磁Ni基板时刻与Dy 4f外时刻反对齐.
- 计算出了3.5 meV的大和正的磁性异构能量 (MAE),表明了超高密度磁性记录的潜力.
- 由于相互竞争的磁性异性质秩序,Dy磁化倾斜.
结论:
- 这项研究为石墨烯/111上的Dy adatoms提供了准确的理论预测,解决了DFT+U的模两可.
- 包括MAE在内的计算磁性属性对于磁性数据存储的潜在应用具有重要意义.
- 这些发现为预测和设计基于稀土的新型磁性纳米结构提供了一条途径.
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