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Evolution of an optical vortex with initial fractional topological charge
V.V. Kotlyar 1,2, A.G. Nalimov 1,2

IPSI RAS – Branch of the FSRC "Crystallography and Photonics" RAS,
443001, Samara, Russia, Molodogvardeyskaya 151,
Samara National Research University, 443086, Samara, Russia, Moskovskoye Shosse 34

 PDF, 2713 kB

DOI: 10.18287/2412-6179-CO-766

Pages: 5-12.

Full text of article: Russian language.

In a number of theoretical (J. Opt. 6, 259 (2004)) and experimental (Opt Express 19, 5760 (2011)) works, an original fractional-TC optical vortex (with TC standing for topological charge) was shown to evolve into an integer optical vortex whose TC is equal to the nearest (i) smaller integer, if the fractional part is smaller than 1/2, and (ii) larger we show that the initial fractional optical vortex evolves into an integer optical vortex with TC equal to the nearest (i) smaller integer, if the fractional part is smaller than 0.12, and (ii) larger integer, if the fractional part is larger than 0.12. This can be explained by the fact that the additional center integer, if the fractional part is larger than 1/2. In this work, using numerical simulation, of singularity is generated on the beam periphery characterized by near zero-intensity (a millionth of the maximum), thus prohibiting the experimental detection, but allowing a numerical assessment.

optical vortex, fractional topological charge, near field, far field.

Kotlyar VV, Nalimov AG. Evolution of an optical vortex with initial fractional topological charge. Computer Optics 2021; 45(1): 5-12. DOI: 10.18287/2412-6179-CO-766.

The work was partly funded by the Russian Foundation for Basic Research grant #18-29-20003 and the RF Ministry of Science and Higher Education within a state contract with the "Crystallography and Photonics" Research Center of the RAS.


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