单个CsPbBr_(3)钙钛矿量子点的荧光闪烁特性  

Photoluminescence blinking properties of single CsPbBr_(3) perovskite quantum dots

作　　者：李斌 苗向阳[1] Li Bin;Miao Xiang-Yang(Key Laboratory of Spectral Measurement and Analysis of Shanxi Province,College of Physics and Information Engineering,Shanxi Normal University,Linfen 041004,China)

机构地区：[1]山西师范大学物理与信息工程学院,原子分子和材料光谱测量与分析山西省重点实验室,临汾041004

出　　处：《物理学报》2021年第20期335-341,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11974229);山西省高等学校科技创新计划(批准号:2021L257)资助的课题。

摘　　要：钙钛矿量子点优异的光学特性使其成为太阳能电池、发光二极管、激光器、探测器等常规光电器件以及单光子源、纠缠光子源等非经典量子光源的理想材料.对于单个钙钛矿量子点荧光闪烁特性的研究可以为微纳光电器件的制备提供技术支撑.针对如何有效分析钙钛矿单量子点的荧光闪烁机制这一关键问题,本文基于荧光轨迹进行亮、暗态的幂律分析发现:弱光激发下钙钛矿单量子点荧光的亮、暗态概率密度服从幂律统计,量子点的荧光闪烁是表面俘获态的活化和非活化造成的;强光激发下,单量子点荧光的亮态概率密度服从指数截断的幂律统计,量子点的荧光闪烁是量子点充、放电和表面俘获共同作用的结果.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 onstate 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.

关 键 词：钙钛矿 单量子点 荧光闪烁 幂律分布 

分 类 号：O469[理学—凝聚态物理] TB383.1[理学—电子物理学]