Fig. 11
a Schematic of the optical set-up used to capture the interference pattern between Gaussian beam (with a small divergence) and optical vortex beam generated by a hologram. Intensity of vortex beams corresponding to topological charges b \(l=-5\), c \(l=-10\) and d \(l=-25\) and their respective interference pattern e \(l=-5\), f \(l=-10\) and g \(l=-25\) captured at the CCD plane. The number of fins in the interference pattern matches with the topological charge