Hanbury Brown–Twiss-type experiments with optical vortices and observation of modulated intensity correlation on scattering from rotating ground glass

Abstract

The famous Hanbury Brown and Twiss type experiments are performed with optical vortices. Though the intensity correlation for vortices are found to be similar to that of the TEM${}_{00}$ mode of the He-Ne laser used to generate the vortices, an interesting difference is observed when they are scattered through a rotating ground glass plate. For smaller time delays, correlations for vortices follow the same pattern as the scattered Gaussian beam of light except that the vortices decay faster and the rate of decay depends on the order of the vortex. For longer time delays, however, the intensity correlation curves for vortices are found to be modulated and this modulation becomes more prominent as the order of the vortex is increased. This seemingly counterintuitive observation is supported by exact analytical results.