Microcavity-enhanced exciton dynamics in light-harvesting complexes : Insights from Redfield theory

Summary, in English

We investigated the exciton transfer dynamics in photosynthetic light-harvesting complex 2 (LH2) coupled to an optical microcavity. Using computational simulations based on Redfield theory, we analyzed how microcavity coupling influences energy relaxation and transfer within and between LH2 aggregates. Our results show that the exciton transfer rate between B850 rings follows a square dependence on the light-matter coupling strength, in agreement with Fermi’s golden rule. Interestingly, the energy transfer rate remains almost independent of the number of LH2 complexes. This behavior is explained by the molecular components of the polaritonic wavefunction overlaps. These findings highlight the crucial role of cavity-induced polaritonic states in mediating energy transport and provide a theoretical framework for optimizing microcavity environments to enhance exciton mobility in light-harvesting systems and related photonic applications.

• Author: Ilmari Rosenkampff; Tõnu Pullerits
• Department/s: Chemical Physics; NanoLund: Centre for Nanoscience; LU Profile Area: Light and Materials; LTH Profile Area: Photon Science and Technology; LTH Profile Area: Nanoscience and Semiconductor Technology
• Publishing year: 2025-07-28
• Language: English
• Publication/Series: Journal of Chemical Physics
• Volume: 163
• Issue: 4
• Links: http://dx.doi.org/10.1063/5.0273374
• Document type: Journal article
• Publisher: American Institute of Physics (AIP)
• Topic: Atom and Molecular Physics and Optics
• Status: Published
• ISBN/ISSN/Other: ISSN: 0021-9606