Photon correlations in the collective emission of hybrid gold-(CdSe/CdS/CdZnS) nanocrystal supraparticles

TL;DR

This study analyzes photon emission statistics from hybrid gold-based nanocrystal supraparticles, revealing antibunching despite multiple emitters and demonstrating collective emission effects through a detailed model.

Contribution

It introduces a model combining F"orster energy transfer and Auger recombination to explain photon antibunching in large supraparticles with collective emission phenomena.

Findings

Antibunching observed despite many nanocrystals involved

Model based on non-coherent energy transfer and Auger recombination explains antibunching

Some supraparticles show short-time bunching indicating collective emission

Abstract

We investigate the photon statistics of the light emitted by single self-assembled hybrid gold-CdSe/CdS/CdZnS colloidal nanocrystal supraparticles through the detailed analysis of the intensity autocorrelation function $g^{(2)}(\tau)$. We first reveal that, despite the large number of nanocrystals involved in the supraparticle emission, antibunching can be observed. We then present a model based on non-coherent F\"orster energy transfer and Auger recombination that well captures photon antibunching. Finally, we demonstrate that some supraparticles exhibit a bunching effect at short time scales corresponding to coherent collective emission.