High‐performance GaAs/AlGaAs graded refractive index separate confinement heterostructure lasers grown by molecular‐beam epitaxy on Si3N4 masked substrates

High‐performance single quantum well graded refractive index separate confinement heterostructure lasers have been grown by molecular‐beam epitaxy on Si3 N4 masked substrates. Lateral optical, carrier, and current confinement is supplied by the faceting which occurs during growth. Stripe lasers fabricated on 10‐μm‐wide openings in the [011] direction have threshold currents as low as 15 mA and internal quantum efficiency of 81% for a 500‐μm‐long cavity.