Plasmon-Coupled Förster Resonance Energy Transfer between Silicon Quantum Dots

The distance dependence of localized surface plasmon (LSP)-coupled Forster resonance energy transfer (FRET) between Si quantum dots (QDs) is experimentally and theoretically investigated utilizing core-shell nanostructures. The dependence of the energy transfer efficiency, rate, and characteristic distance, as well as the enhancement of the acceptor emission, on the shell thickness is examined. Compared to the structure without assistance of LSP from silver nanoparticles (Ag NPs), the FRET rate is enhanced by a factor of 15, and the Forster radius increases by 50% as a result of plasmon-coupling to the Si QDs and the FRET-assisted exciton transfer from the donors to the acceptors. The potential to tune the characteristic energy transfer distance has implications for applications in nanophotonic devices or sensors.