Fig. 1. (a) Generation schematic of AVB. (b) Simulated foci of vortex beam, AB, and AVB. (c) Diameter of ring-shaped focus versus the topological charge of vortex beams, and widths of zeroth-order AB and AVB.

Fig. 2. (a) Experimental setup of AVB-based fabrication system. The right is the simulated intensity distribution along the propagation direction. (b) Simulated and (c) experimentally tested intensity distributions in different planes corresponding to dashed lines shown in (a).

Fig. 3. (a) Phase of AVBs with different zero-order width. (b) Simulation intensity distribution of ring-shaped focus with different diameters. (c) Experimental intensity distribution of ring-shaped focus with different diameters. (d) SEM images of microtubes fabricated by single exposure of AVBs with different diameters. (e) Comparison of processing time between the single-exposure method and single-point scanning method. (f) Comparison of diameters of simulated ring-shaped foci, experimentally tested ring-shaped foci, and fabricated microstructures. Scale bars are 20 µm.

Fig. 4. (a) Generation principle of AVB with fractional topological charge. (b) Simulated gap-ring focus distribution. (c) Experimentally tested gap-ring focus distribution. The topological charges vary from 5.1 to 5.5 in (b) and (c). (d)–(h) SEM images of micro gap rings fabricated by single exposure of gap-ring focus. The top right corners are the corresponding foci. Scale bar is 10 µm. (i) Relationship between the gap size of fabricated microrings and the topological charges.