Cooperative resonance energy transfer in plasmonic systems

We study cooperative effects in energy transfer from an ensemble of donors to an acceptor near a plasmonic nanostructure. We demonstrate that plasmonic coupling between donors changes the energy content of the system and hence dramatically affects transfer of its energy to an outside acceptor. When donors are situated in a close proximity to the metal surface, the transfer is strongly reduced relative to one from independent donors due to additional dissipation caused by plasmon exchange between individual donors. With increasing donors' separation from the metal, dissipation becomes less prevalent and the system transitions to cooperative regime described by plasmonic superradiant and subradiant eigenstates. We find that energy transfer from either one is significantly (similar to 10) more efficient than from independent donors due to much stronger coupling of superradiant states to the acceptor and much weaker damping of subradiant states. We develop a theory for cooperative plasmon-enhanced energy transfer and present numerical results demonstrating the amplification effect for a layer of donors and an acceptor on spherical plasmonic nanoparticle.