Tailoring nondiffracting structured lights along arbitrary three-dimensional trajectories via an inversed design

We develop an inverse-designed caustic approach to tailor nondiffracting structured lights that exhibit arbitrary intensity structures. Simultaneously, these lights can propagate in an accelerated manner along an arbitrary three-dimensional trajectory. The scheme inherently gives rise to caustics, which are intensity singularities in geometric optics. These types of structured lights possess sharp intensity shapes and exhibit a significant intensity gradient. Moreover, these types of structured nondiffracting lights exhibit structured orbital angular momentum. The proposed approach breaks the restriction of conventional nondiffracting light beams, which preserve fixed propagation trajectories and structures. We experimentally validate our theory prediction. These diverse accelerating nondiffracting light beams will pave the way for optically trapping and moving particles along arbitrary three-dimensional trajectories and are likely to result in applications in wavefront control, optical micromachining, and depth imaging.