没有变磁磁磁带在MnF_{2}中分裂
V C Morano1, Z Maesen1, S E Nikitin1
1PSI, Center for Neutron and Muon Sciences, Forschungsstrasse 111, 5232 Villigen, PSI, Switzerland.
Physical review letters
|June 23, 2025
概括
研究人员研究了改变磁体,特别是MnF2,用于预测的性马格农模式. 不弹性中子散射显示没有可观察到的分裂,这表明MnF2表现得像古典的Nel反铁磁体.
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:
- 替代磁铁是一种对直线补偿磁铁的类.
- 替代磁铁的一个关键预测属性是存在分裂的性马格农模式.
- 这些模式最近被认为存在于二化 (MnF2) 中.
研究的目的:
- 实验验证MnF2.2中预测的分裂性马格农模式的存在.
- 通过不弹性中子散射来研究MnF2的自旋动力学.
主要方法:
- 不弹性中子散射实验是在单晶MnF2.2上进行的.
- 测量是在布里卢恩区域的高对称路径上进行的,那里预计将发生裂.
- 由此产生的无弹性光谱是使用各种磁交换相互作用和异性变性来建模的.
主要成果:
- 在实验分辨率内没有检测到可以观察到的马格农模式的分裂.
- 旋转动力学是通过J1,J2,J3近邻交换相互作用和弱单轴异轴性精确建模的.
- 这些主导相互作用比晶格具有更高的对称性,并且变磁分裂相互作用被发现是可以忽略不计的.
结论:
- MnF2的自旋动力学与经典的尼尔反铁磁体无法区分,在布里卢恩区域内具有退化的马格农模式.
- 虽然变磁对称性可能允许性马格农模式,但它们在MnF2中的分裂是微不足道的小.
- 一个磁场在 Γ 点附近诱导了马格农模式的 Zeeman 分裂,但这与预测的磁变分裂有所不同.
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