Evolution dynamics of vortex quasi-Airy beams

We numerically and experimentally investigate the evolution dynamics of quasi-Airy beams with a spiral phase. The impact of a spiral phase on the evolution dynamics of quasi-Airy beams depends on the included angles of the beams, which will result in different propagation directions of the two separated trajectories. The first- and second-moment radii along the x–y axes are utilized to study the beam spreading due to the non-symmetry of the quasi-Airy beams. It is found that, unlike the common Airy beams, the variation of the first moment is not proportional to the topological charge, and it will present some anomalous regularities when the quasi-Airy beams appear quite differently from the common ones. In addition, the second-moment difference between quasi-Airy beams with different topological charges is quite small unless the quasi-Airy beams are close to the common ones. Furthermore, the quasi-Airy beams with a spiral phase are generated experimentally by loading the combined phase patterns into a spatial light modulator directly, and their evolution dynamics are demonstrated in detail. The experimental results are coincident with the numerical results. Our results will help to provide a broad application in trapping atom and optical tweezers.