Auger processes in InGaAs QDs grown by using the droplet method

Abstract

We present the carrier dynamics of InGaAs quantum dots with and without cladding layers grown by heterogeneous droplet epitaxy. Time-resolved photoluminescence spectroscopy showed double exponential decays for the first excited states, including an initial fast decay, of highly excited quantum dots with cladding layers in contrast to the single exponential decay in quantum dots without cladding layers. Moreover, the GaAs barriers had slow rise times of about 220 ps, which corresponded to the initial fast decay time of the first excited states of quantum dots. These results provide evidence of Auger processes between the carriers in the GaAs barriers and those in the first-excited states of quantum dots.