High temperature (T >= 400 K) operation of strain-compensated quantum cascade lasers with thin InAs insertion layers and AlAs blocking barriers

Conventional strain-compensated quantum cascade (QC) lasers are fabricated with both tensile. strained AlInAs and compressively strained GaInAs layers. We show that strain compensation can also be achieved using tensile strained AlInAs barrier layers and lattice-matched GaInAs with thin InAs layers inserted. In the present paper, we use Al(0.6)In(0.4)As as barriers. The tensile strain caused by these barriers is compensated by thin InAs layers inserted into the lattice-matched GaInAs wells. The lasers, mounted epilayer up with as-cleaved facets, operate in pulsed mode up to 400K (127 deg C) at a wavelength of lambda about 5.3 mu m. For a laser with a ridge size of 18 mu m x 3 mm, the maximum output peak power per facet obtained is 1 W at room temperature (27 deg C).