Structural resonances have been found in the Raman spectra of optically levitated liquid droplets of mixtures of water and glycerol. The observed resonances could be assigned by using the well-known Lorenz-Mie formalism. It was found that for the particular droplet under investigation quite high-order numbers (l = 8,9) of the natural modes of oscillation of a sphere play a dominant role. We describe the intensities of the resonances in the Raman spectrum particularly through the volume averaged internal field intensity. We show further that the internal angle-averaged electric field intensity is localized near, but not confined to, the sphere surface.
© 1985 Optical Society of America
Rudolf Thurn and Wolfgang Kiefer, "Structural resonances observed in the Raman spectra of optically levitated liquid droplets," Appl. Opt. 24, 1515-1519 (1985)