埃尔加的磁性结构和旋转重定向
J M Cadogan1, D H Ryan2, R A Susilo1
1School of Science, UNSW Canberra at the Australian Defence Force Academy, Canberra, ACT, BC 2610, Australia.
概括
确定了ErGa的磁性结构,揭示了32K的铁磁秩序. 在16K以下,的磁矩在晶体结构内重新定向,由莫斯巴乌尔光谱学证实.
科学领域:
- 固态物理 固态物理
- 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:
- 像ErGa这样的金属间化合物对于理解磁现象至关重要.
- 众所周知,CrB类型的正方形结构 (Cmcm) 承载着复杂的磁性行为.
- 研究磁性排序和旋转重定向,为基本的磁相互作用提供了洞察力.
研究的目的:
- 为了阐明金属间化合物ErGa.Ga的磁性结构.
- 为了确定磁性排序温度和埃尔比 (Er) 磁矩的方向.
- 通过使用互补的技术来研究旋转转向转向的转变.
主要方法:
- 使用高分辨率的中子粉衍射来确定磁体结构.
- 用Er Mössbauer光谱来支持结构发现并分析超细相互作用.
- 进行了温度依赖的磁性测量,以确定磁性排序和过渡.
主要成果:
- 埃尔加在32(2) K处表现出铁磁顺序,与埃尔时刻最初沿着晶体学b轴对齐.
- 旋转重定向过渡发生在16K以下,在那里,埃尔比亚磁矩从b轴向c轴偏离.
- 在3K时,埃尔的矩是8.7(3) μB,其矩与bc平面内的b轴相距31(3) 度,由Mössbauer数据支持.
结论:
- 已经精确地确定了ErGa的磁性结构,揭示了一个复杂的旋转重定向现象.
- 中子衍射和Mössbauer光谱学证实了温度依赖的磁性行为和矩定向.
- 这项研究有助于理解稀土金属间化合物的磁相互作用.
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