ABSTRACT
The physical principles involved in the operation and design of mid-infrared interband cascade lasers (ICLs) are described. While the cascaded geometry is analogous to those used in quantum cascade lasers (QCLs) and bipolar cascade quantum well lasers, the implementation is unique to the antimonide material system. Quantum confinement is used to tune the overlapping and gapped conduction and valence band states in neighboring electron and hole quantum wells. We discuss the main ingredients necessary to design a high-performance room-temperature ICL and present some highlights from characterization results for narrow-ridge ICLs operating in continuous-wave mode.
