Rapid Fabrication of 3D Chiral Microstructures by Single Exposure of Interfered Femtosecond Vortex Beams and Capillary-Force-Assisted Self-Assembly

The rapid fabrication of 3D chiral microstructures is of great significance in the fields of optics and mechanics. Here, a hybrid strategy is presented that combines spatial-light-modulator-assisted two-photon polymerization (SATPP, top-down) and capillary-force-assisted self-assembly (bottom-up) for efficiently yielding chiral microstructures. Based on SATPP, the pre-subunit can be efficiently fabricated via 3D chiral discrete vortex beam (CDVB), which is generated by interfering multiple parallel vortex beams. Then, the 3D chiral microstructures are assembled by subunits with the aid of meniscus-directed capillary force. This strategy can fabricate stable 3D chiral microstructures and improve the manufacturing efficiency by more than 100 times. Furthermore, the height, diameter, rotation angle, and handedness of chiral microstructure can be flexibly regulated. Because the obvious chiral feature of the manufactured assembly, it can exhibit strong vortical dichroism when excited by the light carrying orbital angular momentums. Also, it can be used to prepare functional microrobots base on the chiral body rotation. This hybrid strategy can rapidly manufacture 3D chiral microstructures, which can be utilized as multifunctional scalable platform with promising prospect in micro/nano robotics, optical sensors, and advanced functional devices.

Automated summary

A hybrid strategy combining spatial-light-modulator-assisted two-photon polymerization (SATPP) and capillary-force-assisted self-assembly is proposed for the rapid fabrication of stable 3D chiral microstructures. This strategy allows for flexible regulation of the microstructure's shape and properties and has promising applications in various fields.