基于CsPbX3无机钙钛矿量子点的超宽带太赫兹调控机理及器件研究

Ultra-wideband dynamic manipulation is the foundation of terahertz wave application in communication, sensing, imaging, biomedicine and so on. It is also a challenging research hotspot and frontier topic in the world. This project proposes an method to realize laser/electric field dual dynamic manipulation for the ultra-wideband (0.1~10THz) terahertz wave based on Si-SiO2-CsPbX3 inorganic perovskite quantum dots. A carrier dynamics theoretical model of the CsPbX3 inorganic perovskite quantum dots induced by external laser/electric field excitation is constructed, and the carriers evolution process in CsPbX3 inorganic perovskite quantum dots is presented by ultrafast and terahertz time-resolved spectroscopy. The dynamic mechanism of the terahertz wave manipulated by the CsPbX3 inorganic perovskite quantum dots is explored. The relationship between the structure and function of CsPbX3 inorganic perovskite quantum dots will be revealed. The optimal synthesis technology of the CsPbX3 inorganic perovskite quantum dots with high optical quality is studied. The dynamic controlling characteristics for terahertz wave in the SOI-CsPbX3 inorganic perovskite quantum dots are tested and analyzed under the condition of external modulated laser/electric field. Finally, the terahertz wave at any frequency point and arbitrary polarization state in ultra-wideband range with GHz response speed is achieved efficiently. The research results provide a theoretical reference for the design and preparation of terahertz device using CsPbX3 perovskite quantum dot film, and promote the application and development of terahertz technology.

超宽带动态调控是太赫兹波在通信、传感、成像及生物医学等领域应用基础，也是国际上极具挑战性的研究热点和前沿课题。本项目提出了利用硅-氧化层-CsPbX3无机钙钛矿量子点结构实现超宽带(0.1~10THz)太赫兹波的光/电双动态调控。构建光/电作用下CsPbX3无机钙钛矿量子点的载流子动力学理论模型，利用超快-太赫兹光谱技术呈现CsPbX3无机钙钛矿量子点中载流子的演变过程，探索其对太赫兹波动态调控机理，揭示CsPbX3无机钙钛矿量子点结构和调控性能的关系。深入研究不同卤素、尺寸、形貌的高光学质量CsPbX3无机钙钛矿量子点最佳合成工艺。测试分析调制激光/电场作用下CsPbX3无机钙钛矿量子点样品对太赫兹波动态调控特性，实现任一频率点、任意偏振态的太赫兹波快速动态调控，响应速度达GHz量级。研究成果为CsPbX3无机钙钛矿量子点薄膜太赫兹器件设计和研制提供理论借鉴，推动太赫兹技术的应用与发展。

太赫兹波动态调控是太赫兹技术在通信、传感、成像及生物医学等领域应用基础，也是国际上极具挑战性的研究热点和前沿课题。本项目开展了基于CsPbX3无机钙钛矿量子点太赫兹动态调控机理及器件研究，完成了高质量CsPbX3无机钙钛矿量子点制备，探索了CsPbX3无机钙钛矿量子点薄膜在外加光激励下载流子传输机理，制作基于CsPbX3无机钙钛矿量子点的超表面复合结构实现了对太赫兹波高速信号调制。设计的双开口金属环-钙钛矿量子点复合结构的太赫兹调制器对太赫兹调制深度达到99%，调制速率可达3.3MHz，同一结构可以实现对多个太赫兹频率调控。研制的双C超材料-钙钛矿量子点复合结构太赫兹调制器实现对太赫兹波调控响应速率为5MHz，调制深度为88.3%，改变双C超材料几何尺寸可以实现对不同频率太赫兹波调控。研制的基于Ω形超材料-钙钛矿量子点复合结构太赫兹调制器，对太赫兹波调制深度达到84%，响应速度为8MHz。设计硅波导-钙钛矿量子点复合结构太赫兹波调制器，该调制器对太赫兹波调制深度为82%，调制速率为6.7MHz，且对入射太赫兹波极化不敏感。利用制作的CsPbX3无机钙钛矿量子点复合结构太赫兹调制器为搭建了太赫兹无线通信系统，实现了高分辨的图像实时传输。