Open AccessPropagation of a topologically half-charge vortex light beam in a self-focusing photorefractive medium
Author(s) -
Chih-Rong Chen,
Chih-Hung Yeh,
Ming-Feng Shih
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.003180
Subject(s) - physics , light beam , optics , optical vortex , photorefractive effect , topological quantum number , beam (structure) , vortex , instability , azimuth , soliton , gaussian beam , light intensity , quantum mechanics , nonlinear system , thermodynamics
While a fundamental Gaussian light beam can form stably a spatial soliton in certain self-focusing medium, a single-wave topologically integer-n-charge vortex light beam cannot. It breaks up into 2n filaments due to symmetry breaking and azimuthal instability, in which every azimuthal section of a π phase range from a soliton and repels itself from its azimuthal neighboring soliton. Then what happens to the half-charge vortex light beam, which contains only one section of a π phase range? We investigate experimentally and theoretically the propagation and stability of a topologically half-charge vortex light beam in a self-focusing photorefractive medium. We observed that the light beam propagates unstably in a self-focusing medium and breaks up into three filaments. This result is confirmed by numerical simulation and perturbation analysis.