基于微纳光学谐振结构及太赫兹Purcell效应的新颖太赫兹源研究

太赫兹技术在多个领域具有重大的应用前景，是近年来国际上的研究热点。但是，当前太赫兹光学的进展仍然受限于紧凑、高效太赫兹源的缺乏。传统基于非线性光学的太赫兹源需要较厚的非线性晶体，并且受到相位匹配条件限制，因此不利于片上应用。在本项目中，我们研究采用谐振波长与泵浦激光一致的领结型纳米光天线结构与高折射率半导体材料的Mie谐振结构用于增强非线性光学效应。两种结构同时与太赫兹谐振器完美整合，结合太赫兹谐振器的Purcell效应用增强太赫兹辐射向自由空间的耦合。整个项目包含理论设计及优化、实验及最终太赫兹辐射测试。本项目目标是采用多波段、多尺度下的两种谐振器协同增强作用，实现新颖的片上太赫兹辐射源，推进太赫兹技术的进一步应用。

Terahertz technology has great promise applications in a variety of areas and remains as a hot topic in recent years. However, to date the progress in terahertz optics is still limited by the lack of compact and highly-efficient terahertz sources. Conventional terahertz emitters based on nonlinear optics need bulk nonlinear crystal and are limited by the phase matching conditions. As a result, they are not suitable for on-chip applications. In this project, we propose to use two kinds of optical resonators with the resonance matching the pump lasers to enhance the nonlinear effect, the bowtie antennas and the Mie resonance structures made from high-index semiconductors. These two optical resonators will be incorporated with terahertz resonators perfectly, and the latter can be used to enhance the coupling of generated terahertz radiations to the free space based on the Purcell effect. The whole project consists of numerical simulations and optimizations, device fabrication and the final characterization of terahertz emission. With these multi-spectral and multi-scale resonators to work collaborately, our project aims at the realization of novel thin-film terahertz sources and push forward the further progress in the applications of terahertz technology.