Self-focusing and defocusing of twisted light in non-linear media.

Max Planck Institute of Microstructure Physics, Halle, Germany.
Optics Express (Impact Factor: 3.55). 12/2010; 18(26):27691-6. DOI: 10.1364/OE.18.027691
Source: PubMed

ABSTRACT We study the self-focusing and defocusing of a light beam carrying angular momentum (called twisted light) propa- gating in a nonlinear medium. We derive a differential equation for the beam width parameter f as a function of the propagation distance, angular frequency, beam waist and intensity of the beam. The method is based on the Wentzel-Kramers-Brillouin and the paraxial approximations. Analytical expressions for f are obtained, analyzed and illustrated for typical experimental situations.

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