Lithography-free metamaterial absorbers: Opinion

Although advancement in nanofabrication provides the opportunity to realize nanoscale geometries with high resolutions, the scalability and repeatability issues limit their large-scale applications. Lithography-free metamaterial absorbers (LFMAs) are a potential route for the upscaling of these designs. With restricted freedom in their synthesis, the importance of the proper material choice is emphasized. Herein, we provide a comprehensive overview of the recently developed LFMAs, from both design and material perspectives, while considering their most promising applications. © 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement