Organic-Inorganic FAPbBr3 Perovskite Quantum Dots as a Quantum Light Source: Single-Photon Emission and Blinking Behaviors

In the past decade, lead halide perovskite nano-crystals or quantum dots (QDs) have attracted keen interest due to their potential applications in many optoelectronic systems. In addition, all-inorganic (CsPbX3) perovskite QDs are suggested to be efficient single photon emitting centers. Herein, we study the photon emission properties of recently synthesized organic-inorganic FAPbBr(3) QDs. Our results show that individual FAPbBr3 QDs can act as good single-photon sources with very low multiphoton emission probability achieved by extremely fast nonradiative Auger recombination. However, they exhibit photodegradation and fluorescence intensity intermittency, called blinking. By analyzing the ON(OFF) duration time distribution, particularly the OFF duration times, we suggest that two types of blinking (type-A and type-B) simultaneously contribute to the blinking behavior of FAPbBr(3) QDs. In type-A and type-B blinking, the ON/OFF periods are attributed to charged/discharged states and to activation/deactivation of fast nonradiative recombination centers, respectively. By analyzing the ON/OFF duration cutoff time as a function of the excitation intensity, we verify that type-A blinking is caused mainly by diffusion-controlled electron transfer, partially accompanied by Auger ionization processes.