在WSe2/WS2异构结构中,扭转角度依赖的动量空间直接和间接介层激子
Jiajun Chen1, Xiaofei Yue1, Yabing Shan1
1State Key Laboratory of ASIC & System, School of Information Science and Technology, Fudan University Shanghai 200433 China.
RSC advances
|June 16, 2023
概括
在WSe2/WS2异构中,扭曲角度控制着层间激子 (ILEs). 研究人员确定了直接和间接的ILE,并使用电场调节了它们的排放,为新的量子应用铺平了道路.
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
- 量子信息科学 量子信息科学
背景情况:
- 范德瓦尔斯 (vdW) 异构结构,特别是II型带对齐过渡金属二甲基化物 (TMDCs),表现出独特的介层激子 (ILEs).
- 这些异构结构中的扭曲角度引入了复杂的IEE细结构,为控制提供了机会,但也带来了挑战.
研究的目的:
- 在WSe2/WS2异构结构中研究具有不同扭转角度的ILEs的演变.
- 识别和描述直接和间接ILEs及其过渡路径.
- 为了证明电场诱导的IEE排放的调节.
主要方法:
- 光发光 (PL) 谱学,包括循环极化和激发功率依赖的测量.
- 密度函数理论 (DFT) 计算来分析带结构和刺激子特性.
- 制造和表征WSe2/WS2异构结构与控制的扭转角度.
主要成果:
- 观察到两种不同的ILE与相反的圆极化,归因于K-K和Q-K过渡路径.
- 通过实验测量和理论计算证实了直接和间接ILE的性质.
- 通过应用外部电场来修改异构结构的带结构来实现IE排放的成功调节.
结论:
- 扭曲角度是控制VDW异构结构中的ILE属性的关键参数.
- 电场操纵提供了一条可行的途径来调整层间激子发射.
- 这项工作促进了对量子技术的TMDC异构结构中扭转角度依赖现象的理解和应用.
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