Enhancement of Energy Transfer between Quantum Dots: The Impact of Metallic Nanoparticle Sizes

We investigated the dependency of plasmonic enhancement of Forster energy transfer between CdSe/ZnS quantum dots on the sizes of metallic nanoparticles as well as the distances between these particles and the quantum dots. The results demonstrate how the interdot Forster energy transfer depends upon the relative magnitudes of (i) the Forster energy transfer rates from the donor and acceptor quantum dots to the metallic nanoparticles, according to their transition frequencies, and (ii) the plasmonic field enhancement at the quantum dot emission frequencies. As a result, even in the absence of the donor-induced plasmonic field, one can adjust these processes to stimulate the interdot energy flow from the donor to acceptor quantum dots, increasing its rate significantly.