We observe phase singularities in the superposed field of two Gaussian beams. It is seen that the formation of these singularities depends on the tilt between two Gaussian beams and the separation of their beam axes. By reversing the angle or the position of the beams, one can change the sign of the vortex. We have shown the formation of single as well as multiple vortices by changing the tilt angle and the position of two Gaussian beams. The experimental results are verified with theoretical analysis. We also observe that such a vortex structure can be formed through superposition of two backreflected Gaussian beams from any optical element with two flat surfaces, as illustrated through a beam splitter and a neutral density filter. This technique is very useful for generation of vortices with high-power lasers where one cannot use a spatial light modulator.
© 2013 Optical Society of America
Diffraction and Gratings
Original Manuscript: June 11, 2013
Revised Manuscript: August 17, 2013
Manuscript Accepted: August 20, 2013
Published: September 13, 2013
Pravin Vaity, A. Aadhi, and R. P. Singh, "Formation of optical vortices through superposition of two Gaussian beams," Appl. Opt. 52, 6652-6656 (2013)