在异构结构中转角度依赖谷极化切换
Danjie Dai1,2, Bowen Fu3, Jingnan Yang3
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Science advances
|May 15, 2024
概括
我们展示了曲范德瓦尔斯异构结构如何控制层间激子 (IXs) 中的谷极化. 这种扭曲工程使未来的valleytronic和twistronic设备的电气控制成为可能.
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:
- 过渡金属二甲基化物异构结构中的莫伊尔超级格子提供了对山谷物理学的控制.
- 层间激子 (IXs) 呈现出对谷电子学至关重要的谷性质.
- 在这些系统中,对山谷偏振的电气控制仍未得到充分探索.
研究的目的:
- 研究谷极化对激发电位的扭转角度依赖的控制.
- 阐明控制山谷极化扭转角度调节的物理机制.
- 展示电控的谷地可定位设备.
主要方法:
- 制造具有控制扭转角度的范德瓦尔斯异构结构.
- 电门用于调节载体密度和刺激子特性.
- 光学光谱检测谷极化和激子动态.
主要成果:
- 证明两极化切换和谷两极化程度与莫伊尔时期的依赖性.
- 确定了刺激电位和电子孔交换相互作用的扭曲角度调制的机制.
- 实现了IXs的扭转角度依赖的山谷两极化.
结论:
- 扭曲角度工程有效地操纵电控异构结构中IXs的谷极化.
- 这些发现为twistronic设备中自由度谷的电气控制提供了一条途径.
- 这项工作为下一代 valleytronic 设备铺平了道路,这些设备具有可调节的特性.
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