Microstructural and interband transition properties of vertically stacked InAs/GaAs self-assembled quantum dots embedded in modulation-doped heterostructures

Abstract

The transmission electron microscopy image and selected area electron diffraction pattern showed that self-assembled InAs quantum-dot (QD) arrays embedded in GaAs barriers were periodically inserted in an Al0.25Ga0.75As/GaAs heterostructure. The temperature-dependent photoluminescence spectra of the InAs/GaAs quantum dots embedded in modulation-doped heterostructures showed interband transitions from the first-excited electronic subband to the first-excited heavy-hole subband together with those from the ground subband to the ground heavy-hole band (E-1-HH1) while the spectra of the InAs/GaAs QDs alone showed only the peak related to the (E-1-HH1) transitions. (C) 2001 American Institute of Physics.