在扭曲的h-BN/石墨烯异构结构中调节的跨带转换
Bingyao Liu1,2,3, Yu-Tian Zhang4, Ruixi Qiao5
1Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China.
Physical review letters
|July 21, 2023
概括
扭曲的六角化 (h-BN) /石墨烯异构结构表现出可调节的电子特性. 扭曲角度影响带结构和带间过渡,为光电设备提供了新的设计可能性.
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:
- 扭曲的六角化 (h-BN) /石墨烯异构结构以其复杂的电子特性而闻名.
- 然而,随机扭转可能导致意想不到的过渡行为影响设备性能.
研究的目的:
- 为了研究h-BN/石墨烯异构结构中扭曲角度依赖的合效应.
- 了解莫雷电位如何影响石墨烯的带结构和带间过渡.
主要方法:
- 使用单色电子能量损失光谱 (MEELS).
- 在h-BN/石墨烯范德瓦尔斯异构结构中分析了取决于扭转角度的合效应.
主要成果:
- 发现莫伊尔电位改变了石墨烯的带结构,导致M点 (高达0.22 eV) 内层过渡中的红移,扭转角度增加.
- 由于h-BN和石墨烯的Brillouin区域相对扭曲,观察到可调节的垂直过渡能量 (5.15.6 eV).
结论:
- 范德瓦尔斯异构结构中的扭曲合效应对于设备制造至关重要.
- 通过扭曲角度连续调节的带间转换为设计光电设备提供了全新的自由度.
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