Picosecond time-resolved photon antibunching measures nanoscale exciton motion and the true number of chromophores

Hedley, G. J. et al. (2021) Picosecond time-resolved photon antibunching measures nanoscale exciton motion and the true number of chromophores. Nature Communications, 12, 1327. (doi: 10.1038/s41467-021-21474-z) (PMID:33637741) (PMCID:PMC7910429)

Abstract

The particle-like nature of light becomes evident in the photon statistics of fluorescence from single quantum systems as photon antibunching. In multichromophoric systems, exciton diffusion and subsequent annihilation occurs. These processes also yield photon antibunching but cannot be interpreted reliably. Here we develop picosecond time-resolved antibunching to identify and decode such processes. We use this method to measure the true number of chromophores on well-defined multichromophoric DNA-origami structures, and precisely determine the distance-dependent rates of annihilation between excitons. Further, this allows us to measure exciton diffusion in mesoscopic H- and J-type conjugated-polymer aggregates. We distinguish between one-dimensional intra-chain and three-dimensional inter-chain exciton diffusion at different times after excitation and determine the disorder-dependent diffusion lengths. Our method provides a powerful lens through which excitons can be studied at the single-particle level, enabling the rational design of improved excitonic probes such as ultra-bright fluorescent nanoparticles and materials for optoelectronic devices.

• Item Type: Articles
• Additional Information: T.E. thanks the Deutsche Forschungsgemeinschaft (German Research Foundation) for funding through Collaborative Grant No. 319559986. F.J.H. thanks the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) for funding through the postdoctoral “booster program” of—Project-ID 314695032—S.F.B. 1277, Project B03. P.T., F.S. and T.S. thank the European Union’s Horizon 2020 research and innovation programme under grant agreement No 737089 (Chipscope) and the DFG under Germany´s Excellence Strategy—EXC 2089/1—390776260 for financial support. Open Access funding enabled and organized by Projekt DEAL.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Hedley, Dr Gordon
• Authors: Hedley, G. J., Schröder, T., Steiner, F., Eder, T., Hofmann, F. J., Bange, S., Laux, D., Höger, S., Tinnefeld, P., Lupton, J. M., and Vogelsang, J.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Nature Communications
• Publisher: Nature Research
• ISSN: 2041-1723
• ISSN (Online): 2041-1723
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Nature Communications 12(1):1327
• Publisher Policy: Reproduced under a Creative Commons License