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arXiv · 1601.02350

A general theorem on the divergence of vortex beams

G. Vallone·G. Parisi·F. Spinello·E. Mari·F. Tamburini·P. Villoresi
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Abstract

The propagation and divergence properties of beams carrying orbital angular momentum (OAM) play a crucial role in many applications. Here we present a general study on the divergence of optical beams with OAM. We show that the mean absolute value of the OAM imposes a lower bound on the value of the beam divergence. We discuss our results for two different definitions of the divergence, the so called rms or encircled-energy. The bound on the rms divergence can be expressed as a generalized uncertainty principle, with applications in long-range communication, microscopy and 2D quantum systems.

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G. Vallone, G. Parisi, F. Spinello, E. Mari, F. Tamburini, P. Villoresi. 2016-01-11. A general theorem on the divergence of vortex beams. https://doi.org/10.1103/physreva.94.023802

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