We report the observation of optical vortices in a laser beam propagating through the stripe pattern of a cholesteric liquid crystal. The liquid crystal is confined in a cell with homogeneous boundary conditions and forms a diffraction phase grating. Optical vortices are produced by edge dislocations of the cholesteric grating. The vortices show up as spots of zero light intensity in the diffraction maxima. There is one spot in each +1 and -1 diffraction maximum and two spots in diffraction maxima +2 and -2. (C) 2000 Optical Society of America. OCIS codes: 160.3710, 050.1940, 180.1790, 070.4690.
This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OL.25.000317. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.
Voloschenko, D.; Lavrentovich, Oleg (2000). Optical Vortices Generated by Dislocations in a Cholesteric Liquid Crystal. Optics Letters 25(5) 317-319. doi: 10.1364/OL.25.000317. Retrieved from https://oaks.kent.edu/cpippubs/347