Heterostructures and infrared emitters with compressed InAsSb layers

An overview is presented of strained InAsSb heterostructures and infrared emitters. InAsSb/InGaAs strained-layer superlattices (SLS) and InAsSb quantum wells were characterized using magneto-photoluminescence and compared with unstrained InAsSb and InAs alloys. In heterostructures with biaxially compressed InAsSb, large quantum confinement energies were observed, and the holes exhibited a decrease in effective mass, approaching that of the electrons. This study demonstrates that the electrons and holes in the InAsSb heterostructures are confined in the InAsSb layers, and the band offsets are type I. A large increase in the Auger-1 threshold energy should accompany the strain-induced change in valence-band symmetry of the InAsSb layers. Correspondingly, the InAsSb heterostructures display high radiative efficiencies and increased activation energies for nonradiative recombination compared with the unstrained alloys. LEDs and L-mrs with InAsSb heterostructure active regions are described. InAsSb/InGaAs SLS LEDs operating at 300K at wavelengths {le} 5 pm have been demonstrated. Optically pumped InAsSb/InGaAs SLS lasers, with InPSb cladding, had a maximum operating temperature of 100K