High-Power, Continuous-Wave 3.0- to 3.5-Micron Emitting Quantum Cascade Semiconductor Laser

The technical objective of this proposal is to demonstrate a Quantum Cascade Laser (QCL) emitting in the 3.0-3.5 & #181;m wavelength region, which employs a metamorphic buffer layer (MBL). It is the goal of this program to develop a QCL single-stripe device which will operate in a single, diffraction-limited lobe under room temperature continuous-wave (CW) operation to moderately high (~ 0.5 W) output powers. The use of the MBL allows for a lower-strain QCL active-region design compared with conventional approaches which employ InP substrates. Advanced conduction-band-engineered QC lasers will be used, since they allow virtual suppression of carrier leakage out of the devices active regions, resulting in electro-optical characteristics much less temperature sensitive than for conventional QCL devices; and thus allowing for significant increases in average power and CW wallplug efficiency.