Ultrabroadband metamaterial perfect absorber operating in ultraviolet to near-infrared regime

Abstract

Designing broadband absorbers has garnered significant attention recently due to their wide range of applications. However, developing absorbers with a simple structure that operate across an extensive optical regime remains challenging. This paper presents a metamaterial absorber with a simple structure that achieves ultrabroadband absorption ranging from 287 to 1544 nm, covering ultraviolet to near-infrared regimes. The absorber consists of periodically arranged dielectric blocks on a metallic slab, and it achieves an absorption efficiency exceeding 90%. This high performance is attributed to the superposition of multiple neighboring resonances. Furthermore, the absorber remains effective at large incidence angles and exhibits polarization independence due to its symmetric configuration. The simplicity of the design not only facilitates fabrication but also makes it suitable for applications in solar energy harvesting, optical imaging, and sensing.