Collective Rayleigh scattering from dielectric particles

An investigation is taking place into a new classical scattering phenomenon called 'collective Rayleigh scattering'. A collection of dielectric particles pumped by a laser radiation field may form a strong density grating on the scale of the radiation wavelength. The particles then coherently scatter the incident radiation. Current theoretical research is confined to collective Rayleigh scattering from particles small compared with the radiation wavelength, for which there are many possible applications in the field of nonlinear optics. However, by considering larger Mie particles, it can be seen that there are also potential applications in the areas of optical particle characterization and discrimination. This paper outlines the theoretical framework of CRS and the first observations from preliminary experiments utilizing a standing-wave gradient force trap.