Ultralow-threshold graded-index separate-confinement single quantum well buried heterostructure (Al,Ga)As lasers with high reflectivity coatings

Abstract

Unlike conventional semiconductor lasers, single quantum well lasers with high reflectively coatings have dramatically reduced threshold currents as a result of the smaller volume of the (active) quantum well region. A cw threshold current of 0.95 mA was obtained for a buried graded-index separate-confinement heterostructure single quantum well laser with facet reflectivities of ∼70%, a cavity length of 250 μm, and an active region stripe width of 1 μm.