Photoluminescence blinking properties of single CsPbBr<sub>3</sub> perovskite quantum dots

Abstract

Owing to their excellent optical properties, perovskite quantum dots become ideal materials for conventional optoelectronic devices such as solar cells, light-emitting diodes, lasers, detectors, and non-classical quantum light sources such as single photon sources and entangled photon sources. The research on the photoluminescence blinking dynamics of single perovskite quantum dots can provide technical support for the preparation of nano-optoelectronic devices. In recent years, some achievements have been made based on the photoluminescence lifetime and photoluminescence intensity of single perovskite quantum dots. In this paper, the bright (on) state probability density and the dark (off) state probability density are extracted from photoluminescence intensity trajectories of single quantum dots and fitted by the (truncated) power-law function. It is found that the on-state probability density of single perovskite quantum dot under weak excitation condition can be fitted by a power-law function, which indicate that the photoluminescence blinking originates from the activation and deactivation of surface trap states. Under strong excitation condition, the on-state probability density of single perovskite quantum dot obeys exponential truncated power-law statistics, which indicate that the photoluminescence blinking is affected not only by the surface trap state, but also by the charging and discharging process.