在双层堆叠磁性半导体中共存的铁电和铁路山谷极化
Yanzhao Wu1, Junwei Tong2, Li Deng1
1Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), School of Material Science and Engineering, Northeastern University, Shenyang 110819, China.
Nano letters
|June 26, 2023
概括
研究人员发现,3R型双层YI2表现出铁路和铁电两极分化,使得新的电子设备可以通过电场或磁场控制山谷两极分化.
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
- 这就是Spintronics.
背景情况:
- 在磁性半导体中铁电和铁路两极的共存对于先进的电子设备至关重要.
- 之前的研究已经在2D材料中探索了个别的铁电或铁路电特性.
研究的目的:
- 为了研究单层和双层YI2.2的磁性和极化特性.
- 探索2D范德瓦尔斯材料中并发铁路和铁电行为的潜力.
- 提出基于这些多铁性质的设备应用.
主要方法:
- 用密度函数理论 (DFT) 的计算来研究电子和磁结构.
- 在不同的堆叠配置中分析磁性排序,山谷偏振和铁电偏振.
- 使用电磁场研究山谷偏振的可调性.
主要成果:
- 单层YI2具有铁磁半导体特性,具有显著的谷极化 (高达105 meV).
- 带有3R型堆叠的BILAYER YI2显示了同时的铁路和铁电两极分化,显示了多铁的行为.
- 在3R型双层YI2中的谷极化可以通过电场 (通过铁电极化反转) 或磁场 (磁化操纵) 控制.
- 在2D范德瓦尔斯LaI2和GdBr2双层中观察到类似的现象.
结论:
- 在3R型双层YI2中发现并发的铁路和铁电两极化,为多功能电子设备开辟了新的途径.
- 证明了山谷偏振的电磁场控制是spintronics和valleytronics的一个重大进步.
- 这项研究为设计具有增强功能的下一代电子元件提供了基本的理解.
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