Electrical injection type-II (GaIn)As/Ga (AsSb)/(GaIn)As single 'W'-quantum well laser at 1.2 μm

Highly efficient interface-dominated electrical injection lasers in the near-infrared regime based on the type-II band alignment in (GaIn)As/Ga(AsSb)/(GaIn)As single 'W'-quantum wells are realised. The structure is designed by applying a fully microscopic theory, grown by metal organic vapour phase epitaxy, and characterised using electroluminescence measurements and broad-area laser studies. A characteristic blue shift of 93 meV/(kA/cm²) with increasing charge carrier density is observed and compared with theoretical investigations. Low threshold current densities of 0.4 kA/cm², high differential efficiencies of 66%, optical output powers of 1.4 W per facet, and internal losses of only 1.9 cm^-1 are observed at a wavelength of 1164 nm for a cavity length of 930 μm. For a cavity length of 2070 μm, the threshold current density is reduced to 0.1 kA/cm². No indication for type-I related transitions for current densities up to 4.6 kA/cm² is observed.