Vortex-antivortex dynamics and singularity splitting in engineered composite vortex beams

We present a comprehensive investigation into the intricate dynamics of vortex-antivortex (V-AV) pairs and the phenomenon of singularity splitting within composite vortex beams (CVBs) engineered by the coaxial superposition of two single-ring Laguerre-Gaussian (LG) modes. By systematically tuning the key engineering parameters-namely the topological charges (TCs), power ratio, and beam waists of the constituent LG beams-we demonstrate precise control over the formation, evolution, and spatial distribution of optical singularities. Our analytical and numerical results reveal that the net TC governs the overall singularity number, while the power and beam waist ratios act as fine-tuning knobs for the trajectories of V-AV dipoles. A central finding of this study is the controlled splitting of a high-order singularity into multiple first-order singularities, a process whose dynamics and final configuration are dictated by the interplay of the aforementioned parameters. This work not only provides a fundamental understanding of singularity physics in complex optical fields but also establishes a robust methodology for the on-demand design and manipulation of multi-singularity landscapes. The ability to engineer such structured light fields paves the way for advanced applications in optical communication, multi-particle manipulation, etc.