Generation of ring-shaped optical vortices in dissipative media by inhomogeneous effective diffusion

TL;DR

This paper demonstrates the controlled generation of various stable ring-shaped optical vortices in dissipative media using inhomogeneous effective diffusion, with potential applications in structured light technologies.

Contribution

It introduces a novel method to generate and control diverse ring-shaped optical vortices via inhomogeneous diffusion in the complex Ginzburg-Landau model.

Findings

Stable square- and gear-shaped optical vortices were generated.

Shape and stability of vortices can be tuned by diffusion parameters.

New types of ring-shaped optical vortices with potential applications were identified.

Abstract

By means of systematic simulations we demonstrate generation of a variety of ring-shaped optical vortices (OVs) from a two-dimensional input with embedded vorticity, in a dissipative medium modeled by the cubic-quintic complex Ginzburg-Landau equation with an inhomogeneous effective diffusion (spatial-filtering) term, which is anisotropic in the transverse plane and periodically modulated in the longitudinal direction. We show the generation of stable square- and gear-shaped OVs, as well as tilted oval-shaped vortex rings, and string-shaped bound states built of a central fundamental soliton and two vortex satellites, or of three fundamental solitons. Their shape can be adjusted by tuning the strength and modulation period of the inhomogeneous diffusion. Stability domains of the generated OVs are identified by varying the vorticity of the input and parameters of the inhomogeneous diffusion. The results suggest a method to generate new types of ring-shaped OVs with applications to the work with structured light.