Ridge waveguide InGaN/GaN quantum dot edge emitting visible lasers

摘要

Blue‐emitting and green‐emitting laser heterostructures were grown by molecular beam epitaxy, incorporating InGaN/GaN quantum dots as the active medium, with a measured quantum efficiency of 60% on n‐GaN bulk substrates. These quantum dots exhibit no S‐shape in the photoluminescence peak wavelength as a function of temperature, as typically found in comparable quantum well devices. The lasers were characterized by a threshold current density, J th , of 930 A/cm 2 under pulsed bias, with a differential efficiency of 13.9%, and a wall plug (power conversion) efficiency of 0.4% at 1050 A/cm 2 . Green‐emitting quantum dot lasers have J th = 935 A/cm 2 . The lasers were also characterized by their modal properties through near field imaging (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)