STRUCTURAL RESONANCES IN THE TOTAL RAMAN-SCATTERING AND FLUORESCENCE-SCATTERING CROSS-SECTION - CONCENTRATION-PROFILE DEPENDENCE

Single and double structural resonances in the total Raman- or fluores cence-scattering cross section of spherical dielectric particles are t heoretically investigated. We found appreciable differences in the res onance heights and in the distributions of the sources of the Raman-sc attered light inside the particle for the emission of dipoles induced parallel to the exciting field (p = alpha E), designated as directed e mission, and the emission of orientation-averaged dipoles. The influen ce of radial symmetric concentration profiles on Raman or fluorescent scattering in the case of the excitation of double structural resonanc es is investigated. We show that the resonance heights and the radial positions associated with the spherical layers probed by the resonance s depend on the concentration profiles, the mode type of the resonance s? and the emission characteristics (directed or orientation-averaged emission) of the probed molecules. (C) 1996 Optical Society of America .