Far-field modulation of fluorescence decay rates in pairs of oriented semiconducting polymer nanostructures

We report on the observation of far-field dipole-dipole coupling in pairs of uniformly z-oriented polymer nanostructures manifested as a fluorescence lifetime modification (both enhancement and suppression relative to isolated particles) modulated by interparticle separation. The observed oscillatory modulation in the fluorescence decay rate as a function of interparticle distance (ranging from $200$ to ≈20000.3em0exnm) results from modification of the vacuum field at the position of the probe dipole by the presence of the second radiating dipole. These results provide observation of a dipole-dipole interaction in the ``inductance'' interparticle distance scale between the near field (≈2000.3em0exnm) and far field (>5000.3em0exnm), important for the realization of efficient active nanophotonic devices.