Broadband, High-Reflectivity Dielectric Mirrors at Wafer Scale: Combining Photonic Crystal and Metasurface Architectures for Advanced Lightsails.

Highly ambitious initiatives aspire to propel a miniature spacecraft to a neighboring star within a human generation, leveraging the radiation pressure of lasers for propulsion. One major challenge for this enormous feat is to build a meter-scale, ultralow mass lightsail with broadband reflectivity. In this work, we present the design and fabrication of a lightsail composed of two distinct dielectric layers with photonic crystal/metasurface structure covering a 4" wafer.