在没有铁磁体的氧化物异构结构中的电荷转移诱导的界面铁磁
Jie Zheng1,2, Wenxiao Shi1,2, Zhe Li1,2
1Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
ACS nano
|March 11, 2024
概括
研究人员使用CaRuO3和LaNiO3超晶格在氧化物异构中诱导铁磁性. 这种新兴的属性源于界面电荷转移,导致共享的基里温度和可调的磁性异构性.
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
- 氧化物异构结构 氧化物异构结构
背景情况:
- 氧化物异构结构由于强烈的层间合而表现出独特的特性.
- 界面铁磁性可以出现在由非铁磁性氧化物组成的异构结构中.
研究的目的:
- 为了研究CaRuO3/LaNiO3超网格中介面铁磁相的诱导.
- 了解新出现的铁磁力背后的机制及其与电子结构的关系.
主要方法:
- 制造具有不同厚度子层的CaRuO3/LaNiO3超级网格.
- 使用X射线吸收光谱 (XAS) 来探测电荷转移的表征.
- 对X射线线性二重化 (XLD) 光谱进行分析,以确定轨道占用率和磁性异构性.
主要成果:
- 在CaRuO3和LaNiO3亚层中建立了铁磁秩序,其基里温度为75K.
- 在接口上,XAS揭示了Ru向Ni的显著电荷转移,诱导了超交换相互作用.
- XLD表示偏好的d-轨道占用 (d3为Ru,d为Ni),影响磁性异质.
结论:
- 电荷转移是驱动这些氧化物异构结构中的界面铁磁的主要机制.
- 该研究展示了一种方法,可以在以前非铁磁材料中产生铁磁性质.
- 这为设计具有定制磁性功能的氧化物材料提供了一条途径.
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