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Digital sorting of Hermite-Gauss beams: mode spectra and topological charge of a perturbed Laguerre-Gauss beam
A.V. Volyar 1, E.G. Abramochkin 2, Yu. Egorov 1, M. Bretsko 1, Ya. Akimova 1

Physics and Technology Institute of V.I. Vernadsky Crimean Federal University,
Simferopol, Republic of Crimea, Russia,
Samara Branch of P.N. Lebedev Physical Institute of Russian Academy of Sciences, Samara, Russia

 PDF, 1365 kB

DOI: 10.18287/2412-6179-CO-747

Pages: 501-509.

Full text of article: Russian language.

We developed and implemented an intensity moments technique for measuring amplitude and initial phase spectra, the topological charge (TC) and orbital angular momentum (OAM) of the Laguerre-Gauss (LG) beams decomposed into the basis of Hermite-Gaussian (HG) modes. A rigorous theoretical justification is given for measuring the TC of unperturbed LG beams with different values of radial and azimuthal numbers by means of an astigmatic transformation on a cylindrical lens. We have shown that the measured amplitude and phase spectra of the HG modes make it possible to find the orbital OAM and TC, as well as digitally sorting the HG modes and then restoring the initial singular beam.

diffraction optics, orbital angular momentum, intensity moments technique.

Volyar AV, Abramochkin EG, Egorov YuA, Bretsko MV, Akimova YaE. Digital sorting of Hermite-Gauss beams: mode spectra and topological charge of a perturbed Laguerre-Gauss beam. Computer Optics 2020; 44(4): 501-509. DOI: 10.18287/2412-6179-CO-747.

The work was funded by the Russian Foundation for Basic Research under RFBR research project No. 19-29-01233.


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