Radiative and non-radiative photokinetics alteration inside a single metallic nanometric aperture

We resolve the photokinetic rates enhancement of Rhodamine 6G molecules diffusing in a water-glycerol mixture within a single nanometric aperture milled in an opaque aluminium film. Combining fluorescence correlation spectroscopy and lifetime measurements, we report the relative influence of excitation, radiative and non-radiative decay in the fluorescence process, giving a detailed description of the physics behind the overall 15 fold enhancement of the average fluorescence rate per molecule. This procedure is broadly adaptable to a wide range of nanostructures.