Fast spontaneous emission and high Förster resonance energy transfer rate in hybrid organic/inorganic plasmonic nanostructures


We report an experimental study of the plasmon-assisted spontaneous emission and the Förster resonance energy transfer between organic molecules and semiconductor colloidal quantum dots. The localized plasmonic field in the nanogap between a gold nano-popcorn's tips and a 5-nm separated gold film supports high photonic density of states and provides pathways for the light-matter interaction mechanisms. We demonstrate that, besides the total enhanced decay rate up to 66 times for quantum dots and molecules, the Förster resonance energy transfer efficiency and rate constant are simultaneously modified. While the energy transfer efficiency is reduced from 84% to 35% due to the non-radiative quenching effect and fast donor decay rate, the energy transfer rate constant is significantly increased from 4 to 20 ns-1. Our results have quantitatively elucidated decay mechanisms that are important toward understanding and controlling of the light-matter interaction at the nanoscale.

Publication Title

Journal of Applied Physics