Abstract

Continuing our studies of ultra-low threshold injection lasers based on self-organized vertically coupled quantum dots (VECODs) [1-3] we have studied the possibility of achievement of lasing via states of InAs VECODs placed into InGaAs matrix as an active layer of a separate confinement laser heterostructure grown on InP (100) substrate The experimental wafer includes 3 sheets of such dots formed at 500 °C and separated by 5 nm thick InGaAs spacers. It was shown using TEM that lateral size of quantum dots (QDs) significantly exceeds that of InGaAs/GaAs dots and makes about 50 nm. At the same time vertical size of them is even slightly less than in InGaAs/GaAs system and is equal to only 4-5 nm. The density of dots is 8·10⁹cm⁻² [4].

© 1998 IEEE