Study of Electron-Vibrational Interaction in Molecular Aggregates Using Mean-Field Theory: From Exciton Absorption and Luminescence to Exciton-Polariton Dispersion in Nanofibers

Abstract

We have developed a model in order to account for electron-vibrational effects on absorption, luminescence of molecular aggregates and exciton-polaritons in nanofibers. The model generalizes the mean-field electron-vibrational theory developed by us earlier to the systems with spatial symmetry, exciton luminescence and the exciton-polaritons with spatial dispersion. The correspondence between manifestation of electron-vibrational interaction in monomers, molecular aggregates and exciton-polariton dispersion in nanofibers is obtained by introducing the aggregate line-shape functions in terms of the monomer lineshape functions. With the same description of material parameters we have calculated both the absorption and luminescence of molecular aggregates and the exciton-polariton dispersion in nanofibers. We apply the theory to experiment on fraction of a millimeter propagation of Frenkel exciton polaritons in photoexcited organic nanofibers made of thiacyanine dye.

Long‐Range Fluorescence Propagation in Amyloidogenic β‐Sheet Films and Fibers

“…However, this overlap is usually very limited to a narrow spectral band of approximately a dozen nanometers and occurs owing to the overlap of the FL and OA tails, in which OA has a very low value, decreasing by a factor of 10 from the OA maximum. [ 46,47,54 ]…”

Effects of Electron-Vibrational Interaction in Polariton Luminescence: Non-Markovian Fano Resonances and Hot Luminescence

“…In this work we focus on polariton luminescence bearing in mind two types of molecular systems based on organic dyes: H-aggregates and enhanced green fluorescent protein (eGFP). Experimental 1 and theoretical 27 results show that the dipole-dipole interaction between molecules,…”

“…In Refs. 25,27 we developed a mean-field electronvibrational theory of Frenkel EPs in organic dye structures including the systems with spatial symmetry (like organic molecular crystals), and applied it to the aggregate absorption, luminescence and the EPs with spatial dispersion. The matter is that ordered structures include among other things also organic dye nanofibers 1,3 that are synthesized by self-assembly of thiacyanine (TC) dye molecules in solution.…”

“…In Ref. 27 we restricted ourselves to the exciton luminescence. Polariton luminescence in cavity was calculated using numerical solution of coupled equations of motion 28 , balance equations 23 or Langevin approach where dissipation is added as Lindblad terms 29 .…”

“…In this work we use non-Markovian model of molecular relaxation, Ref. 25,27 , to calculate non-equilibrium polariton luminescence, i.e. the polariton luminescence line-shape during relaxation.…”