2.08 THz and 4.96 THz Room-Temperature Quantum Cascade Lasers Based on Non-Polar M-Plane ZnMgO/ZnO

We report on numerical study of room-temperature terahertz quantum cascade lasers (THz QCLs) based on a nonpolar m-plane ZnMgO/ZnO employing a 2-well design scheme with variable barrier heights and a delta-doped injector well. We show that by varying and optimizing constituent layer widths and doping level of the injector well, high power performance of THz QCLs can be achieved at room temperature: optical gain and radiation frequency is varied from 108 cm−1@ 2.18 THz to 300 cm−1 @ 4.96 THz. These results show that among II-VI compounds the ZnMgO/ZnO material system is optimally suited for high-performance room-temperature THz QCLs.