Experimental and theoretical investigation of loss of coherence on scattering of a beam with helical wavefront

Theoretical and experimental investigations of the second order intensity coherence for a beam with helical wavefront i.e. an optical vortex scattered through a rotating ground glass have been reported. The results have been compared with scattering of the Gaussian beam of a He–Ne laser. It shows that the second order intensity coherence or intensity correlation curve for the vortex decreases much faster than that of the Gaussian beam of the He–Ne laser. We attribute this behaviour to the helicity of the wavefront.

Research highlights
► Experimental and theoretical study of dynamic light scattering with optical vortices.
► Results compared with a Gaussian laser beam for a model system of rotating ground glass.
► Intensity correlation found to decrease faster for an optical vortex.