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V.V. Kotlyar

443001, Samara, Russia, Molodogvardeyskaya 151,

**DOI: **10.18287/2412-6179-CO-858

**Pages: **490-496.

**Full text of article:** Russian language.

**Abstract:**

In optical data transmission with using vortex laser beams, data can be encoded by the topo-logical charge, which is theoretically unlimited. However, the topological charge of a single sepa-rate vortex is limited by possibilities of its generating. Therefore, in this work, we analyze light beams with an unbounded (countable) set of optical vortices. The summary topological charge of such beams is infinite. Phase singularities (isolated intensity nulls) in such beams typically have a unit topological charge and reside equidistantly (or not equidistantly) on a straight line in the beam cross section. Such beams are form-invariant and, on propagation in space, change only in scale and rotate. Orbital angular momentum of such multivortex beams is finite, since only a finite number of optical vortices fall into the area, where the Gaussian beam has a notable intensity. Other phase singularities are located in the periphery (and at the infinity), where the intensity is almost zero.

**Keywords**:

optical vortex, topological charge, shape-invariant beam, multivortex beam, orbital angular momentum.

**Citation**:

Kotlyar VV. Optical beams with an infinite number of vortices. Computer Optics 2021; 45(4): 490-496. DOI: 10.18287/2412-6179-CO-858.

**Acknowledgements**:

This work was supported by the Russian Foundation for Basic Research under project No. 18-29-20003 (Section "Gaussian beam with a vortex-argument cosine envelope function"), the Russian Science Foundation under project No. 18-19-00595 (Section "Gaussian beam with a vortex-argument Bessel envelope function"), and the RF Ministry of Science and Higher Education within a government project of FSRC "Crystallography and Photonics" RAS (Section "Shape-invariant Gaussian beams").

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