来自布洛赫振荡的果曲率光谱.
Christophe De Beule1,2, E J Mele1
1Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Physical review letters
|November 24, 2023
概括
具有较大的周期性的人工晶体在电场下表现出布洛赫振荡. 它们的光学响应共振在太赫兹频率,与贝里曲率组件相关.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 固态物理 固态物理
- 材料科学是一种材料科学.
背景情况:
- 像莫雷超级晶体这样的人造晶体提供可调节的电子特性.
- 布洛赫振荡是量子力学现象,在电场下的周期电位中发生.
- 特拉赫兹 (THz) 频率与先进的光谱学和电子学有关.
研究的目的:
- 为了研究受静电场影响的人造晶体的光学反应.
- 探索布洛赫振荡与共振光学现象之间的联系.
- 从理论上建模THz光学响应及其与材料性质的关系.
主要方法:
- 使用半古典乐队预测理论.
- 在静电场下分析莫雷超级网的光学反应.
- 计算穿着的霍尔导电性及其对贝里曲率的依赖.
主要成果:
- 光学响应显示了Bloch振荡频率在THz模式中的共振.
- 穿着的霍尔导电的共振与贝里曲率的格子富里埃元件成正比.
- 在有效的蜂格子上使用低能耗模型进行演示.
结论:
- 静电场可以在人造晶体中诱导THz频共振.
- 贝里曲率的富里埃元件是这些THz光学共振的关键决定因素.
- 这项工作为设计具有定制THz响应的材料提供了理论框架.
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