Effects of charge accumulation on the photocurrent and photoluminescence characteristics of self-assembled InAs/GaAs quantum dots

We report the results of photocurrent and bias-dependent photoluminescence (PL) in self-assembled InAs/GaAs quantum dots (QDs). The behaviour of the PL intensity at different QD emission energies as a function of the applied electric field show that the QDs are affected by charge accumulation effects. Experimental evidence of a dynamical process of dots charging and discharging of electrons and holes being stored within deeper confinement potential of the QDs is demonstrated.