Observation of Structure Resonances in the Fluorescence Spectra from Microspheres

Abstract
Sharp intensity peaks are observed in the fluorescence spectra from dye-impregnated single polystyrene microspheres which are not seen in the spectra from bulk material. The resonant peaks are shown to correspond to the natural modes of oscillation of a dielectric sphere, and excellent correlation is found between experimental and theoretically predicted spectra. The results can be applied to the interpretation of inelastic emission (fluorescence and Raman) spectra obtained for the chemical speciation of aerosols and particulates.