Emission properties of heterostructures with a (GaAsSb-InGaAs)/GaAs bilayer quantum well

The specific features of the emission characteristics of GaAs-based heterostructures with a GaAs1 - x Sb (x) -In (y) Ga1 - y As bilayer quantum well are studied. The heterostructures are grown by metal-organic chemical vapor deposition (MOCVD). With an analysis of previously reported data on the MOCVD growth process taken into account, the temperature range (560-580A degrees C), the relation between the fluxes emitted by the sources of Group-V and -III elements (a parts per thousand(2)1), and the order of layer growth for the production of the active region of a GaAs/InGaP laser heterostructure are determined experimentally. The active region is a GaAs0.75Sb0.25-In0.2Ga0.8As bilayer quantum well. For the structure, a 1075-nm electroluminescence signal attributed to indirect transitions between the valence band of the GaAs0.75Sb0.25 layer and the conduction band of the In0.2Ga0.8As layer is observed. An increase in the continuous-wave pump current yields a decrease in the 1075-nm emission intensity and initiates stable lasing at a wavelength of 1022 nm at a threshold current density of 1.4 kA cm(-2) at room temperature. Lasing occurs at transitions direct in coordinate space.