Distance Independence in Excitonic Transport Between Chromophores Facilitated by Plasmonic Nanorods

In this study, long-range excitation energy transfer (EET) between molecular aggregates in the presence of plasmonic silver nanorods is explored. Transition matrix elements of biological chromophore complexes are shown to be greatly enhanced when located near the surface of silver nanoparticles, notably demonstrating distance-independent electronic coupling up to several tens of micrometers. We show that these enhancements can lead to energy transfer rates increased by up to a billion-fold across the entirety of the visible spectrum and into the near-infrared. These results illustrate that it is possible to devise plasmonic nanostructures such that the electronic properties of multi-chromophoric systems can be drastically perturbed by the spatio-inhomogeneous electromagnetic fields generated by them, allowing for EET well beyond the Förster limit.