Carrier dynamics in short wavelength self-assembled InAs/Al0.6Ga0.4As quantum dots with indirect barriers

We report the results of time-integrated and time-resolved photoluminescence (PL) spectroscopy on red-emitting self-organized InAs/Al0.6Ga0.4As quantum dots with indirect barriers. The time-resolved PL measurements confirm that carriers excited in the Al0.6Ga0.4As barriers are initially scattered to the X states and are then captured by the dots on a timescale of 45–60 ps, leading to efficient red emission. The dynamics of the PL decay time are consistent with a carrier hopping process between dots, a result also supported by time-integrated PL experiments.