Simulation Study of the Effect of Surface Plasmon Coupling on Forster Resonance Energy Transfer Behavior

The effect of surface plasmon (SP) coupling of an Ag sphere on the behavior of the Forster resonance energy transfer (FRET) from a donor dipole into an acceptor nearby is numerically studied with the feedback effect of SP resonance field on the radiation behavior of the donor dipole included. In particular, by assigning an intrinsic FRET efficiency for the case of radial dipole orientation with the donor-acceptor separation at 5 nm, we can evaluate the radiated and absorbed (by the Ag sphere) powers, and the power transferred from the donor into acceptor under the condition of SP coupling. Dipole orientations in the radial and tangential directions with respect to the Ag sphere and two Ag sphere-donor separations are considered for comparing their FRET behaviors. Although the SP coupling reduces FRET efficiencies in the spectral ranges around the SP resonance peaks, the powers transferred from the donor into acceptor are generally increased in certain spectral ranges through SP coupling. This behavior can be observed under both dipole orientation conditions and in either case of large or small Ag sphere-donor separation.

Automated summary

The effect of surface plasmon coupling on FRET behavior is studied numerically, considering the feedback effect of the SP resonance field. It is found that SP coupling can increase the power transferred from the donor into acceptor in certain spectral ranges.