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arXiv · 1309.3095

Propagation of an arbitrary vortex pair through an astigmatic optical system and determination of its net topological charge

Salla Gangi Reddy·Shashi Prabhakar·A Aadhi·J. Banerji·R. P. Singh
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Abstract

We embed a pair of vortices with different topological charges in a Gaussian beam and study its evolution through an astigmatic optical system, a tilted lens. The propagation dynamics is explained by a closed-form analytical expression. Furthermore, we show that a careful examination of the intensity distribution at a predicted position past the lens can provide us with the net charge present in the beam. To the best of our knowledge, our method is the first non-interferometric technique to measure the net charge of an arbitrary vortex pair. Our theoretical results are well supported by experimental observations.

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Salla Gangi Reddy, Shashi Prabhakar, A Aadhi, J. Banerji, R. P. Singh. 2013-09-12. Propagation of an arbitrary vortex pair through an astigmatic optical system and determination of its net topological charge. https://doi.org/10.1364/josaa.31.001295

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