Fluorescence intermittency in self-assembled InP quantum dots

Fluorescence intermittency in InP self-assembled dots is investigated by me ans of far field imaging and single dot spectroscopy. Based on our observat ion that blinking dots are found in the vicinity of scratches and the blink ing frequency is drastically enhanced under a near-infrared laser irradiati on, we attribute the origin of the fluorescence intermittency to a local el ectric field due to a carrier trapped at a deep localized center in the Ga0 .5In0.5P matrix. The validity of this explanation is confirmed by a thermal activation-type behavior of the switching rate and artificial reproduction of the blinking phenomenon by an external electric field.