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arXiv · 1511.06009

Robust self-trapping of vortex beams in a saturable optical medium

Albert S. Reyna·Georges Boudebs·Boris A. Malomed·Cid B. de Araújo
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Abstract

We report the first observation of robust self-trapping of vortex beams propagating in a uniform condensed medium featuring local saturable self-focusing nonlinearity. Optical vortices with topological charge m=1, that remain self-trapped over ~ 5 Rayleigh lengths, are excited in carbon disulfide using a helical light beam at 532 nm and intensities from 8 to 10 GW/cm^2. At larger intensities, the vortex beams lose their stability, spontaneously breaking into two fragments. Numerical simulations based on the nonlinear Schrödinger equation including the three-photon absorption and nonpolynomial saturation of the refractive nonlinearity demonstrate close agreement with the experimental findings.

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Albert S. Reyna, Georges Boudebs, Boris A. Malomed, Cid B. de Araújo. 2016-01-02. Robust self-trapping of vortex beams in a saturable optical medium. https://doi.org/10.1103/physreva.93.013840

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