Decorrelation of multiple scattering for an arbitrary scattering angle

Multiple scattering currently presents a major limitation for intensity correlation spectroscopy of quasi-elastically scattered light from concentrated colloidal systems. Theoretical treatments have been restricted to low orders of multiple scattering. Experimentally, suppression of multiple scattering by dual-beam cross-correlation setups has been restricted to a 90-deg fixed scattering angle. We propose a variable scattering angle cross-correlation scheme and present the results of a successful experiment on a highly concentrated aqueous suspension of polystyrene spheres.