An Integrative Statistical Approach for Analyzing Photoluminescence Fluctuations in Single CsPbBr₃ Quantum Dots

Photoluminescence (PL) fluctuations in single quantum dots (QDs), first observed decades ago, continue to hinder their use as stable emitters. Traditional analyses of single-QD PL fluctuations rely on a subset of QDs, raising concerns about sample representativeness. To address this challenge, we developed an integrative statistical analysis to extract common PL fluctuation behaviors across a sample from individual QD data. The method employs the mixture hidden Markov model (MHMM), which assumes shared PL intensity states but allows cluster-specific transition dynamics. The model identified two distinct clusters in CsPbBr3 perovskite QDs characterized by “blinking” and “flickering”, each associated with different transition matrices and PL lifetimes. These findings point to varying carrier trapping mechanisms among the CsPbBr3 QDs. This integrative approach provides a more objective and robust assessment of PL fluctuations and can be extended to investigate the impact of varying composition and surface chemistry on the recombination pathways in perovskite QDs.