通过在人造圆柱旋转中直接观察诱导的磁顺序通过系统格子障碍
Timothy Cote1,2, Amanda K Petford-Long1,2, Charudatta Phatak1,2
1Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA. cd@anl.gov.
Nanoscale
|June 26, 2023
概括
研究人员探索了格子几何学如何影响人工旋转器 (ASI) 中的磁性排序. 无序的ASI显示地面状态能量更接近理想状态,可以控制磁性行为.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 纳米技术纳米技术
背景情况:
- 格子几何学极大地影响了凝聚物质系统中的相变.
- 人工旋转器 (ASI) 是工程制造的纳米磁铁网格,用于研究磁性排序和挫折.
- 在ASIs中控制格子几何学允许研究它们对磁现象的影响.
研究的目的:
- 系统地调查形人造旋转器 (ASI) 中障碍的影响.
- 探索不同的格子几何结构,从周期到随机,如何影响磁性排序和挫折.
- 了解几何顺序参数与磁域行为之间的关系.
主要方法:
- 使用五个顶点图案的组合制造罗姆布斯ASIs.
- 研究四个不同对称度的几何形状 (周期性,准周期性,随机性).
- 使用洛伦兹传输电子显微镜 (LTEM) 进行磁域分析.
- 微磁模拟用于定量格子能量分析.
主要成果:
- 周期性和六倍双胞胎格子中的磁域行为是由强烈合的岛链所决定的.
- 无序的网格表现出磁性行为,其中以高配置退化率的顶点图案为主.
- 无序的ASI的旋转去磁状态在能量上比其他几何体更接近理想化的基本状态.
结论:
- 在ASIs中的几何障碍为控制磁性行为提供了一条途径.
- 设计者混乱系统中的退化和磁性挫折可以用于定制的磁化.
- 这项研究提供了通过人工自旋系统中受控障碍对工程磁性质的洞察.
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