Biexciton-Like Auger Blinking in Strongly Confined CsPbBr3 Perovskite Quantum Dots

08 March 2023, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Single perovskite quantum dots (QDs) are notorious for their poor stability. As a result, surface defects will be generated and this will lead to trion formation that reduces fluorescence intensity, setting barriers to exploring the intrinsic exciton dynamics and the applications of perovskite QDs in single-photon sources. Here we demonstrate that strongly confined CsPbBr3 perovskite QDs (SCPQDs) embedded in a matrix formed by phenethylammonium bromide exhibit suppressed trion formation and remain photostable under intense photoexcitation. The increased surface passivation and stability enables the study of multi-exciton interactions in SCPQDs. We found that, in well-passivated SCPQDs, increasing excitation rates leads to weak fluorescence intensity fluctuations accompanied by an unusual spectral blueshift in the photoluminescence. We attribute this to a biexciton-like Auger interaction between excitons and trapped excitons formed by surface lattice elastic distortions. This hypothesis is corroborated by the unique repulsive biexciton interaction in SCPQDs. Our study provides insights into the fundamental multi-exciton interactions in SCPQDs and will advance the development of quantum light sources based on perovskite QDs.


Perovskite Quantum Dot
Blinking Suppression
Auger Recombination
Trapped Exciton
Single-Photon Emission

Supplementary materials

Supporting Information
Additional STEM images, fluorescence microscopy images, second-order correlation plots, ensemble absorption and PL spectra, blinking traces, occurrence histograms, FLID heatmaps, duration statistics, single of various states in SCPQDs and large CsPbBr3 NCs, time-dependent PL spectra of SCPQDs and II-VI QDs; Scheme of the fluorescence microscope setup.


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.