Investigation of AlxGa1–xAs injection heterolasers emitting visible radiation

An investigation was made of the spectral, threshold, power, and time characteristics of laser diodes of planar and stripe geometry with Al_xGa_1–xAs double heterostructures. The threshold current densities in the Al02Gao8As lasers were 0.9 kA/cm² at 77°K and 6 kA/cm² at 300°K; these densities depended on the solid-solution composition in the active region. The output power of the planar diodes reached 8.2 W at 77°K and 3.6 W at 300°K; their differential efficiency was 0.5 and 0.22 at 77 and 300°K, respectively. The output power of the stripe lasers was 0.75 W per pulse and the differential efficiency was 0.26 at 77°K. The lifetime of electron-hole pairs was estimated under spontaneous and coherent emission conditions at 77 and 300°K.