Photopolymerization with light fields possessing orbital angular momentum: Generation of helical microfibers

Abstract

Photopolymerization is a powerful technique to create arbitrary micro-objects with a high spatial resolution. Importantly, to date all photopolymerization studies have been performed with incident light fields with planar wavefronts and have solely exploited the intensity profile of the incident beam. We investigate photopolymerization with light fields possessing orbital angular momentum, characterized by the topological charge . We show both experimentally and theoretically that, as a consequence of nonlinear self-focusing of the optical field, photopolymerization creates an annular-shaped vortex-soliton and an associated optical fiber, which breaks up into solitons or microfibers. These microfibers exhibit helical trajectories with a chirality determined by the sign of due to the orbital angular momentum of the light field and form a bundle of helical-microfibers. This research opens up a new application for light fields with orbital angular momentum, and our generated microfibers may have applications in optical communications and micromanipulation.