Coupled rate equation modeling of self-assembled quantum dot photoluminescence

We have investigated the quantum dot (QD) carrier capture mechanism using continuous wave photoluminescence as a function of the optical excitation intensity using a sample with a QD density gradient across its surface ranging from 0 to 1.8 £ 10 cm. Modelling of the carrier kinetics has been described by a set of three coupled rate equations associated with the carrier population in the GaAs barrier, wetting layer, and QDs. Through the model we have obtained calculated values to the QD density dependence of the carrier capture rates by the QDs. q 2003 Elsevier Science Ltd. All rights reserved.