DEMULTIPLEXING OF OPTICAL BEAM WITH USING OF RAMAN-NATH ACOUSTO-OPTIC DIFFRACTION AND SINGULAR ACOUSTIC BEAM.

It has been shown that the acousto-optic Raman-Nath diffraction on the acoustic wave, which bears an acoustic vortex, is accompanied by the appearance of the diffraction maxima that bear an optical vortex. The charge of the vortices that appears as a result of the diffraction corresponds to the order of diffraction if the incident optical beam is the Gaussian beam and the charge of the acoustic vortex is equal to unity. When the incident optical vortex beam takes part in this process, the charge of the diffracted optical vortices is shifted on the charge value of the incident optical beam. As a result of the analysis, we obtained the relation for the charge of vortices of diffraction maxima. It has been found that the described effect can be used for controlled demultiplexing. [ABSTRACT FROM AUTHOR]