多模干涉结构太赫兹量子级联激光器的研究

Terahertz quantum-cascade lasers （THz QCL）are key components in THz applications. THz QCLs with high output power and high beam quality are very attractive since they can improve the performance of present THz systems. In this project, a new design of THz QCL based on 1x1 multimode interference structure has been presented. Compared to the traditional rectangular or taper waveguide design, the proposed QCL structure has larger gain area with equal device length, and emits single transverse mode signal suppressing higher order lateral modes excitation which can improve beam quality and collection efficiency, while maintains the advantages of multimode interference devices, such as compact size, ease of fabrication and integration. The design theory and method of multimode interference active device in terahertz region where the dimension of waveguide is comparable to the operating wavelength will be built in the project. The proof-of-principle devices utilizing bound–to-continuum active region structure, can be fabricated with standard semiconductor fabrication process. The feasibility and excellent performance of the proposed structure will be also verified in this project. THz QCLs with the proposed new structure will be the bases of broadband THz communication and high-speed real time THz imaging applications.

太赫兹量子级联激光器（THz QCL）是THz波应用的关键器件。具有高输出功率和高光束质量的THz QCL的对提升THz系统性能有巨大帮助，是研究重点关注方向。本项目提出研制基于1x1多模干涉结构的THz QCL原理型器件。与以往矩形条及楔形波导结构THz QCL不同，新型器件由于相同器件长度下增益面积更大，因而具有更高的出光功率；能够有效抑制高阶侧模激发，输出单横模光，提高光束质量和收集效率，还具有易集成、易制作、结构紧凑的特点。本项目将建立THz波段、亚波长或近波长波导尺寸上多模干涉有源器件的设计理论与方法，采用束缚态到连续态跃迁的有源区结构，完成原理型器件的制作并对器件的可行性和优势加以验证。项目研制的新型THz QCL有望为宽带THz通信和高速THz实时成像等应用奠定基础。

太赫兹量子级联激光器（THz QCL）是THz波应用的关键器件。具有高输出功率和高光束质量的THz QCL的对提升THz系统性能有巨大帮助，是研究重点关注方向。本项目提出研制基于1x1多模干涉结构的THz QCL原理型器件。与以往矩形条及楔形波导结构THz QCL不同，新型器件由于相同器件长度下增益面积更大，因而具有更高的出光功率；能够有效抑制高阶侧模激发，输出单横模光，提高光束质量和收集效率，还具有易集成、易制作、结构紧凑的特点。本项目将建立THz波段、亚波长或近波长波导尺寸上多模干涉有源器件的设计理论与方法，采用束缚态到连续态跃迁的有源区结构，完成原理型器件的制作并对器件的可行性和优势加以验证。项目研制的新型THz QCL有望为宽带THz通信和高速THz实时成像等应用奠定基础。