Studies of whispering gallery modes of single, coated microspheres by steady-state and time-resolved laser fluorescence microscopy

Dye coated single silica and barium titanate microcavities exhibit the whispering gallery modes (WGMs) in their fluorescence spectra. These modes are extremely sensitive to the size, shape and refractive index of the microcavity as well as of the coating thickness (mantle). Theoretical simulations on WGM have been carried out based on the Aden and Kerker model of Lorentz-Mie theory. The effects of the mantle thickness and the surrounding medium on WGMs have been studied. The variation in the decay times of dye molecules with the microcavity size and the mantle thickness have been studied. © 2009 IOP Publishing Ltd.