InAs/InGaAs quantum dot laser with high ground-state modal gain grown by solid-source molecular-beam epitaxy

Abstract

InAs self-organized quantum dots covered w i t h kI033&.6& layer have been grown on GaAs substrates by solid-source molecular beam epitaxy. The effect of the InGaAs thickness has been discussed. As-cleaved 2.54-mm-Iong laser diode using triple stacks of InAs QDs covered with 6.0 ML, I ~. & a 0 . 6 7 A s layer demonstrates a lasing wavelength of 1,214 nm and a threshoid current density of 124A/cm2. The ground-state saturation gain of 23cm-' is achieved due to an energy spacing of 85 meV between the ground and the first excited quantum dot levels and the high dot density.