In this work we investigate the scattering spectra of nonspherical particles. Specifically, the scattering from single isolated microscopic bispheres is measured. We are interested in the changes in the structure resonances spectra as a result of the interaction between the two spheres. The experiment has been carried out on suspended bispheres of polystyrene, glass and Al//2O//3. Levitation is achieved using an electrodynamic balance. Broadband visible excitation is provided by a xenon arc lamp. The 90 degree scattering from the particle is collected with a lens and focused on the entrance slit of a 0. 3 meter grating spectrometer equipped with an optical multichannel analyzer. Visible structure resonances spectra from these particles are presented along with photomicrographs of the suspended particles studied. The photomicrographs reveal features in the local field that are not discernible in the far field scattering measurments. One of these features is the presence of a 'hot spot' where the two spheres are touching. This 'enhanced' field is not present for all spheres investigated. Analysis of the structure resonances data is presented.
|Original language||English (US)|
|Title of host publication||Unknown Host Publication Title|
|Number of pages||1|
|State||Published - 1986|
ASJC Scopus subject areas