Optical characteristics of 1.24-μm InAs quantum-dot laser diodes

The optical characteristics of the first laser diodes fabricated from a single-InAs quantum-dot layer placed inside a strained InGaAs QW are described. The saturated modal gain for this novel laser active region is found to be 9-10 cm/sup -1/ in the ground state. Room temperature threshold current densities as low as 83 A/cm
²
for uncoated 1.24-μm devices are measured, and operating wavelengths over a 190-nm span are demonstrated.