Ag colloids and arrays for plasmonic non-radiative energy transfer from   quantum dots to a quantum well
  Ag nanoparticles in the form of colloids and ordered arrays are used to demonstrate plasmon-mediated non-radiative energy transfer from quantum dots to quantum wells with varying top barrier thicknesses. Plasmon-mediated energy transfer efficiencies of up to ~25% are observed with the Ag colloids. The distance dependence of the plasmon-mediated energy transfer is found to follow the same d^{-4} dependence as the direct quantum dot to quantum well energy transfer. There is also evidence for an increase in the characteristic distance of the interaction, thus indicating that it follows a F\"orster-like model with the Ag nanoparticle-quantum dot acting as an enhanced donor dipole. Ordered Ag nanoparticle arrays display plasmon-mediated energy transfer efficiencies up to ~21%. To explore the tunability of the array system, two arrays with different geometries are presented. It is demonstrated that changing the geometry of the array allows a transition from overall quenching of the acceptor quantum well emission to enhancement, as well as control of the competition between the quantum dot donor quenching and energy transfer rates. 
Graham P. Murphy, John J. Gough, Luke J. Higgins, Vasilios D.   Karanikolas, Keith M. Wilson, Jorge A. Garcia Coindreau, Vit...
physics.optics