不同类型驱动的旋转重定向,以及在立方半导体旋Cr0.1Mn0.9Fe0.2Co1.8O4中的两步磁性排序
A D Singha1, M S Seehra2, M Skoulatos3
1Department of Physics, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India.
概括
这项研究揭示了230 K的立方旋转中铁磁性排序,然后在150 K的旋转重定位.磁性集群和低旋转的状态有助于其独特的磁性半导体特性.
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
- 固态化学 固态化学
背景情况:
- 立方螺旋是复杂的磁性材料,具有多样化的应用.
- 了解磁性排序,旋转重定向和电子性质的相互作用对于开发新的磁性材料至关重要.
研究的目的:
- 为了研究立方旋转子Cr0.1Mn0.9Fe0.2Co1.8O4.4的磁性行为.
- 阐明磁性排序的性质,旋转重定位,以及磁性集群的作用.
主要方法:
- 磁化 (M),电感应 (χ) 和热容量 (CP) 的测量.
- 中子衍射,同步衍射和X射线吸收光谱学用于结构特征.
- 对温度依赖的磁性和对磁性敏感性的分析.
主要成果:
- 在TC=230K以下观察到的铁磁顺序,在TSR ≈150K时旋转重定位.
- 强制性和异质性场随着温度的增加而减少,在TSR以上变得可以忽略不计.
- 有证据表明弱相互作用的磁束和B位点上的CO3+离子的低旋转S=0状态.
- 确定的交换常量 (J/kB = 7.9 K, 22.6 K, -5.3 K) 和带间距为 ~0.57 eV.
结论:
- 该材料表现出复杂的磁性行为,包括铁磁性和场诱导的旋转重定位.
- 弱相互作用的磁束和低旋转的状态是这种磁性半导体的关键特征.
- 远程磁性排序在转重定向温度TSR以下完成.
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