Competition between Förster Resonance Energy Transfer and Donor Photodynamics in Plasmonic Dimer Nanoantennas

22 Avril 2016 , Rédigé par JW

Competition between Förster Resonance Energy Transfer and Donor Photodynamics in Plasmonic Dimer Nanoantennas

Plasmonic nanoantennas provide powerful means to concentrate light into nanoscale dimensions and enhance the fluorescence from single quantum emitters. However, the effects of a resonant plasmonic antenna on Förster resonance energy transfer (FRET) between single molecules remained elusive so far. We address this challengein a recent ACS Photonics publication, and report FRET between single donor and acceptor fluorescent molecules deterministically located inside the nanogap of a resonant gold dimer antenna.

Significance:

- While previous works were limited to moderate nanophotonic effects and lacked position control of the dyes, our gold antennas provide 10x stronger photonic effects on accurately positioned donor and acceptor molecules. This sets unprecedented conditions to explore the limits of nanophotonics to control energy transfer at the nanoscale.

- We conclusively demonstrate enhanced energy transfer rate constants in resonant plasmonic nanoantennas, in good agreement with numerical simulations.

- Our results exemplify the competition between radiative and non-radiative processes in complex nanophotonic systems and highlight geometrical parameters and design rules to optimize nanoantennas for non-radiative energy harvesting.