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Title: The Kuramoto–Lohe model and collective absorption of a photon
Light absorption by molecular exciton states in disordered networks is studied. The main purpose of this paper is to look at how phases of the intermediate ground–excited state superposition interfere during the absorption process. How does this phase average enable, or suppress, absorption to a delocalized state? To address this question, a theory for phase oscillators is used to predict the purity of the collective excited state of the network. The results of the study suggest that collective absorption by molecular exciton states requires a sufficiently large electronic coupling between molecules in the network compared to the random distribution of transition energies at the sites, even when the molecular network is completely isolated from the environment degrees of freedom. The ‘dividing line’ between absorption to a mixture of, essentially, localized excited states and coherent excitation of a pure delocalized exciton state is suggested to be predicted by the threshold of phase synchronization.  more » « less
Award ID(s):
2211326
NSF-PAR ID:
10390357
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Volume:
478
Issue:
2265
ISSN:
1364-5021
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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