Broadband complex-amplitude metasurfaces for arbitrary engineering of spatial caustics
Year: 2026
Type: article
Abstract: We present a broadband complex-amplitude metasurface for generating optical spatial caustics with arbitrary trajectories and transverse profiles. The required field at the metasurface plane is calculated from the target caustic geometry using a Fourier-space interference model that incorporates light-cone, Nyquist, phase-sampling, and aperture constraints. Its performance is evaluated by scalar angular-spectrum propagation and validated through finite-difference time-domain simulations of the full metasurface. Both shape-preserving and morphing caustics follow a prescribed parabolic trajectory. Designed at 1064 nm with a 420 nm period, the metasurface preserves recognizable crescent profiles from 920 to 1060 nm without redesign, offering a compact platform for broadband three-dimensional caustic engineering.
Source: Optics Express
DOI: 10.1364/oe.615891
Authors: Zian Yan, Lei Chen, Qiming Zhang
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,270
OpenAlex ID: W7204817227