在铁磁氧化物绝缘体上对石墨烯进行调的旋转极化状态
Junxiong Hu1,2, Yulei Han3,4, Xiao Chi1,5
1Department of Physics, National University of Singapore, Singapore, 117542, Singapore.
Advanced materials (Deerfield Beach, Fla.)
|October 9, 2023
概括
这项研究显示了石墨烯中强大的旋转极化,在没有磁场的情况下实现了大而可调节的旋转分裂能量. 这一突破推动了二维自旋电子和下一代自旋设备的发展.
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
- 纳米技术纳米技术
背景情况:
- 由于其自旋特性,二维 (2D) 材料对于二维自旋电子非常重要.
- 石墨烯是一种正规的二维材料,具有有限的自旋特性和可调性.
- 开发具有大和可调节的自旋分裂能量的材料对于自旋电子学至关重要.
研究的目的:
- 为了证明在石墨烯中具有强大的和可调节的旋转分裂能量的强大的旋转极化.
- 为了研究旋转极化诱导的机制.
- 探索调整自旋分裂能量的方法.
主要方法:
- 石墨烯和Tm3Fe5O12 (铁磁氧化物绝缘体) 之间的磁交换相互作用.
- 为了确认,使用X射线磁圆二元体 (XMCD).
- 舒布尼科夫-德-哈斯 (SdH) 振荡分析,通过兰道风扇图来测量旋转分裂能量.
- 第一个原则和机器学习计算用于验证.
- 场冷却用于调整旋转分裂能量.
主要成果:
- 在石墨烯中出现了强大的自旋极化.
- 在零磁场下,大而可调节的旋转分裂能量高达132meV.
- 旋转分裂能量可通过场冷却在98至166meV之间调节.
- 实验结果与理论计算一致.
结论:
- 与Tm3Fe5O12接口的石墨烯表现出显著的旋转极化和可调节的旋转分裂能量.
- 这些发现适用于其他二维材料和异构结构.
- 这项工作有可能开发下一代旋转逻辑和内存设备.
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