Abstract

InGaAs strained quantum well lasers with emission wavelengths longer than GaAs lasers are of current interest because their threshold current densities J_th can be substantially lower than those of GaAs lasers of similar structure. The reduction in Jth is produced b the compressive strain in the InGaAs active layer, which reduces the effective density of states of the valence band. Experimentally, however, the reduction in J_th has not been as large as predicted. In addition, InGaAs lasers with emission wavelengths ~1 µm have had much lower differential quantum efficiencies η_d and characteristic temperatures To than GaAs devices.

© 1990 Optical Society of America