  We experimentally measure and analytically describe the fluorescence
enhancement obtained by depositing CdSe/CdS nanocrystals onto a gold plasmonic
crystal, a two-dimensional grating of macroscopic size obtained by gold
deposition on a self-assembled opal. We show evidences of nanocrystals
near-field coupling to the gold Surface Plasmons Polaritons (SPP) followed by
grating-induced SPP re-emission to far-field. We develop a theoretical
framework and an original method in order to evaluate, from photoluminescence
experiments, the SPP extraction efficiency of a grating.

Optics