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arXiv · cond-mat/0006452

Excitonic Funneling in Extended Dendrimers with Non-Linear and Random Potentials

Abstract

The mean first passage time (MFPT) for photoexcitations diffusion in a funneling potential of artificial tree-like light-harvesting antennae (phenylacetylene dendrimers with generation-dependent segment lengths) is computed. Effects of the non-linearity of the realistic funneling potential and slow random solvent fluctuations considerably slow down the center-bound diffusion beyond a temperature-dependent optimal size. Diffusion on a disordered Cayley tree with a linear potential is investigated analytically. At low temperatures we predict a phase in which the MFPT is dominated by a few paths.

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Subhadip Raychaudhuri, Yonathan Shapir, Vladimir Chernyak, Shaul Mukamel. 2000-06-28. Excitonic Funneling in Extended Dendrimers with Non-Linear and Random Potentials. https://doi.org/10.1103/physrevlett.85.282

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