Reliability of strain-balanced Ga0.331In0.669As∕Al0.659In0.341As∕InP quantum-cascade lasers under continuous-wave room-temperature operation

The reliability of high power strain-balanced Ga0.331In0.669As∕Al0.659In0.341As∕InP intersubband quantum cascade lasers (QCLs) emitting at a wavelength of 4.6μm has been studied. Constant current aging is reported for two randomly selected high-reflectivity-coated QCLs with an output power over 100mW. QCLs are tested under continuous-wave operation at a heat sink temperature of 298K(25°C) corresponding to an internal temperature of 378K (105°C). Over 4000h of continuous testing is reported without any decrease in output power.