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arXiv · 2311.15542

Arbitrary Engineering of Spatial Caustics with 3D-printed Metasurfaces

Xiaoyan Zhou·Hongtao Wang·Shuxi Liu·Hao Wang·John You En Chan·Cheng-Feng Pan·Daomu Zhao·Joel K. W. Yang·Cheng-Wei Qiu
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Abstract

Caustics occur in diverse physical systems, spanning the nano-scale in electron microscopy to astronomical-scale in gravitational lensing. As envelopes of rays, optical caustics result in sharp edges or extended networks. Caustics in structured light, characterized by complex-amplitude distributions, have innovated numerous applications including particle manipulation, high-resolution imaging techniques, and optical communication. However, these applications have encountered limitations due to a major challenge in engineering caustic fields with customizable propagation trajectories and in-plane intensity profiles. Here, we introduce the compensation phase via 3D-printed metasurfaces to shape caustic fields with curved trajectories in free space. The in-plane caustic patterns can be preserved or morphed from one structure to another during propagation. Large-scale fabrication of these metasurfaces is enabled by the fast-prototyping and cost-effective two-photon polymerization lithography. Our optical elements with the ultra-thin profile and sub-millimeter extension offer a compact solution to generating caustic structured light for beam shaping, high-resolution microscopy, and light-matter-interaction studies.

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Xiaoyan Zhou, Hongtao Wang, Shuxi Liu, Hao Wang, John You En Chan, Cheng-Feng Pan, Daomu Zhao, Joel K. W. Yang, Cheng-Wei Qiu. 2023-11-27. Arbitrary Engineering of Spatial Caustics with 3D-printed Metasurfaces. https://arxiv.org/abs/2311.15542

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