Research Progress of Semiconductor Interband Cascade Lasers

As an important frontier in the 3-5 gm 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.