Abstract
We calculate the topological charge (TC) of a coherent axial superposition of different-"color" Laguerre-Gaussian (LG) beams, each having a different wavelength and TC. It is found that the TC of such a superposition is equal to the TC of the longer-wavelength constituent LG beam regardless of the weight coefficient of this beam in the superposition and its corresponding TC. It is interesting that the instantaneous TC of such a superposition is conserved and the (time-averaged) intensity distribution of the "colored" optical vortex changes its light "gamut": whereas in the near field with increasing radius, colors of the light rings (rainbow) change according to their TC in the superposition from the smaller TC to the larger one, upon free-space propagation (to the far field), with increasing radius, the ring colors in the rainbow get arranged in the reverse order from the larger TC to the smaller one. It is also shown that choosing the wavelengths (blue, green, and red)in a special way in a three-color superposition of single-ringed LG beams allows obtaining a time-averaged white light ring at a certain distance.
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
