OPTICAL AND MICROWAVE PERFORMANCE OF GAAS-ALGAAS AND STRAINED LAYER INGAAS-GAAS-ALGAAS GRADED INDEX SEPARATE CONFINEMENT HETEROSTRUCTURE SINGLE QUANTUM WELL LASERS

GaAs-AIGaAs and strained layer In0.3Ga0.7As-GaAs-AI-GaAs graded index separate confinement heterostructure single quantum well lasers were grown by molecular beam epitaxy. The strained layer lasers have threshold currents of 12 mA for 3 µm × 400 µm devices (1000 A/cm2) and threshold current densities of 167 A/cm2 for 150 µm × 800 µm devices. The threshold currents of strained layer InGaAs lasers are lower than those of GaAs lasers for all dimensions tested with 20 µm wide GaAs devices exhibiting threshold currents three times those of In0.3Ga0.7As devices. Microwave modulation of 10 µm × 500 µm strained layer lasers with simple mesa structures yields bandwidths of 6 GHz. For all dimensions tested, strained layer InGaAs devices have greater bandwidths than GaAs devices. These measurements confirm theoretical predictions of the effects of valence band modification due to biaxially compressive strain. © 1990 IEEE