Influence of modulation parameters on the self-focusing characteristics of rectangular Airy vortex beam

This study investigates the self-focusing characteristics of a rectangular Airy vortex beam (RAVB) via phase modulation. Numerical simulations are conducted to examine the influence of modulation parameters, including linear factor (c), topological charge (l) and wavelength (λ) on RAVB self-focusing characteristics. The focus depth, focus spot size and peak intensity of RAVB can be effectively controlled via the modulation parameters. Among these parameters, c has the most significant impact on RAVB self-focusing characteristics. As c increases from 4 to 8, the focus depth changes from 8 cm to 41 cm, while the peak intensity increases to 50 times. Although variations in l and λ also contribute to increases in both focus depth and peak intensity, their effects are relatively minor compared to those of c.