半导体带间级联激光器研究进展

半导体带间级联量子阱是实现3~5μm波段中红外激光器的重要前沿,其在半导体光电器件技术、气体检测、医学医疗以及自由空间光通信等诸多领域具有重要科学意义和应用价值。半导体带间级联量子阱发光机理是以二类量子阱中的电子与空穴的带间辐射复合发光为主导,再通过电子注入区与空穴注入区形成级联放大,实现多个量子阱周期内电子与空穴的重复利用。本文综述了半导体带间级联激光器从提出能带结构、外延材料到器件制备技术的发展历程,剖析了器件结构各功能区基本概念和工作原理,介绍了器件结构设计与制备工艺技术难点的里程碑突破,详细解释了载流子再平衡、分别限制层等设计,最后展望了半导体带间级联激光器的发展方向和趋势。

Research Progress of Semiconductor Interband Cascade Lasers

As an important frontier in the 3--5 μm mid-infrared lasers, semiconductor interband cascade quantum well laser has important scientific significance and application value in many fields, such as semiconductor optoelectronic device technology, gas detection, medical science, and free space optical communications. The emission mechanism of semiconductor interband cascade quantum well is dominated by the interband emission combination of electrons and holes in the Type-Ⅱ quantum wells, and then cascade amplification is formed in the electron injection region and the hole injection region, so as to realize the reuse of electrons and holes in multiple quantum well periods. In this paper, the development history of semiconductor interband cascade lasers, from the proposed band structure, epitaxial materials to device fabrication technology, was reviewed, and the basic concepts and working principles of each functional area in a device structure were analyzed. Furthermore, the milestone breakthroughs in the design of device structures and the technical difficulties of fabrication process were introduced, and the designs such as rebalancing of carriers and separate confinement layer were explained in detail. Finally, the development direction and trend of semiconductor interband cascade lasers were forecast.