四角形和立方相的共存诱导了CoMn2O4纳米粒子中的复杂磁性行为
Sanjna Rajput1, Manish Yadav1, Taranga Dehury1
1School of Materials Science and Technology, Indian Institute of Technology (BHU), Varanasi, Uttar Pradesh, 221005, India.
Nanotechnology
|July 4, 2023
概括
这项研究研究了氧化 (CoMn2O4) 纳米粒子,揭示了结构依赖的磁性特性. 观察到不寻常的交换偏差和垂直磁化转移,这表明了先进磁记录技术的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术纳米技术
背景情况:
- 氧化 (CoMn2O4) 具有多种应用,但其结构依赖的磁性属性仍未得到充分探索.
- 了解晶体结构和磁性行为之间的关系对于设计先进的磁性材料至关重要.
研究的目的:
- 为了合成和描述CoMn2O4纳米粒子.
- 为了研究这些纳米粒子的结构依赖的磁性特性.
- 探索 CoMn2O4 在磁记录技术中的潜力.
主要方法:
- 简单的共降技术用于纳米粒子合成.
- 使用X射线衍光度计,X射线光电子光谱 (XPS),拉曼光谱和传输电子显微镜进行表征.
- 磁性测量包括温度依赖的磁化和强制性.
主要成果:
- 瑞特维尔德精炼证实了四边形 (91.84%) 和立体 (8.16%) 旋转相与特定的阴离子分布的共存.
- 通过XPS和拉曼光谱,证实了旋结构和阴离子氧化状态.
- 观察到两个磁过渡 (Tc1=165 K,Tc2=93 K),分别与立方相和四角相相关.
- 检测到不寻常的温度依赖的强制性,显著的自发和常规交换偏差,以及在5K时2.5emu g-1的高垂直磁化转移 (VMS).
- 该VMS归因于雅菲特-基特尔旋转结构和非直线Mn3+和直线四面体旋转之间的竞争.
结论:
- 这项研究阐明了CoMn2O4纳米颗粒的复杂结构依赖的磁性特性.
- 像交换偏差和VMS这样的观察到的现象,为旋转结构内的旋转相互作用提供了洞察力.
- 高VMS表明了CoMn2O4在彻底改变超高密度磁记录技术方面的巨大潜力.
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