旋转轨道驱动的铁磁在半摩尔填充在魔法角度扭曲的双层石墨烯
Jiang-Xiazi Lin1, Ya-Hui Zhang2, Erin Morissette1
1Department of Physics, Brown University, Providence, RI 02912, USA.
概括
扭曲石墨烯中强大的电子相关性和旋转轨道合 (SOC) 产生了绝缘体的铁磁体. 这使得2D电子系统中的电控磁性成为可能.
科学领域:
- 凝聚物质物理学
- 材料科学
- 二维材料
背景情况:
- 强大的电子相关性和旋转轨道合 (SOC) 显著影响材料的电子性质.
- 在扭曲的二维材料中, 莫伊尔超级格子是独一无二的电子现象.
研究的目的:
- 研究电子相关性和SOC对二维电子系统的联合效应.
- 探索相关绝缘状态的稳定及其磁性特性.
主要方法:
- 在魔法角扭曲双层石墨烯和二化物之间制造原子接口.
- 电子属性的表征,包括异常的霍尔效应测量.
- 在平面和垂直电场的应用探测磁顺序.
主要成果:
- 由于moiré平带中的强电子相关性,在四分之一和一半填充时的相关绝缘状态的稳定.
- 由SOC诱导的Mott类绝缘体转化为铁磁体,通过异常的霍尔效应得到证实.
- 演示旋转和谷自由度之间的合,使磁顺序的控制.
结论:
- 电子相关性和SOC工程师在扭曲石墨烯系统中的铁磁作用.
- 可以通过电磁场调节的磁顺序提供了一个实验途径.
- 在moiré带和相关的二维材料中设计拓性能的潜力.
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