The CFS engineers the intrinsic radiative decay rate of low quantum yield fluorophores

The radiative decay rate of weakly fluorescent species was investigated by the Center for Fluorescence Spectroscopy (CFS). An increase in the fluorescence intensity for a low Q0 species was observed by placing a high quantum yield fluorophore and a low quantum yield fluorophore above silver islands deposited on quartz microscope slides. The quantum yield and lifetime equations predict a modification in the radiative decay rate of fluorophores, which has been considered as being independent on the fluorophores' oscillator strength and only weakly dependent on its local environment. It was observed that if close proximity of a metal reduces the lifetime ten fold, the incident intensity can increase tenfold before depletion of the ground state.