ABSTRACTStrained-layer InGaAs/GalnAsP/GalnP separate-confinement-heterostructure quantum well lasers emitting at 980 nm have been developed. The lowest threshold current densities obtained for the single-quantum-well and three-quantum-well lasers are 72 and 150 A/cm2, respectively. The internal quantum efficiency is as high as 94 %, and the internal waveguide loss 5.4 cm−1. The transparency current density and gain coefficient are 33 A/cm2 per well and 0.091 μm A−1, respectively. High characteristic temperatures ranging from 220 to 280 K was obtained. The vertical and lateral full-width at half-maximum of the far-field pattern of the ridge waveguide laser are 47° and 13°, respectively. The results are comparable with the best values reported for the InGaAs/AlGaAs lasers.
