Observation of state filling effects in the carrier dynamics of self-assembled quantum dots

Abstract

The time-resolved photoluminescence technique of picosecond excitation correlation has been applied to self-assembled InGaAs quantum dots grown in the Stranski-Krastanow mode. The nonlinear cross-correlation signal is shown to be due to filling of the quantum dot ground state causing an increase in recombination from the first excited state with increasing carrier density. Carrier relaxation times and radiative as well as non-radiative recombination times for the ground and the first excited state of the quantum dot system are determined using a model based on state filling effect.