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arXiv · 1505.05485

Optical signatures of quantum delocalization over extended domains in photosynthetic membranes

Christopher A. Schroeder·Felipe Caycedo-Soler·Susana F. Huelga·Martin B. Plenio
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Abstract

The prospect of coherent dynamics and excitonic delocalization across several light-harvesting structures in photosynthetic membranes is of considerable interest, but challenging to explore experimentally. Here we demonstrate theoretically that the excitonic delocalization across extended domains involving several light-harvesting complexes can lead to unambiguous signatures in the optical response, specifically, linear absorption spectra. We characterize, under experimentally established conditions of molecular assembly and protein-induced inhomogeneities, the optical absorption in these arrays from polarized and unpolarized excitation, and demonstrate that it can be used as a diagnostic tool to determine the coherent coupling among iso-energetic light-harvesting structures. The knowledge of these couplings would then provide further insight into the dynamical properties of transfer, such as facilitating the accurate determination of Förster rates.

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Christopher A. Schroeder, Felipe Caycedo-Soler, Susana F. Huelga, Martin B. Plenio. 2015-08-10. Optical signatures of quantum delocalization over extended domains in photosynthetic membranes. https://doi.org/10.1021/acs.jpca.5b04804

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