A visible (AlGa)As heterostructure laser grown by molecular beam epitaxy

Abstract
Visible (AlGa)As double‐heterostructure lasers with a 200‐Å Al0.17Ga0.83As active layer have been prepared by molecular beam epitaxy. The diodes lase at ∼7520 Å and have an average pulsed threshold current density Jth of 810A/cm2, which agrees for the first time with the value calculated from first principles without adjustable parameters by Casey, Jr., in the very thin active‐layer regime. The far‐field half‐power full‐width ϑd in the direction perpendicular to the junction plane is as narrow as 11 °. The temperature coefficient T0 of the temperature dependence of threshold is 110 K.