Full spectrum ultra-wideband absorber with stacked round hole disks

In this paper, we design a stacked round hole disk absorber, the simulation and calculation are done by FDTD Solutions. We demonstrate absorber with ultra-wideband absorption in full spectrum (0.25–4 µm). Due to plasmon resonance, the absorption rate of the absorber in the 3450 nm spectral range (0.25–3.7 µm) is more than 90% with an average absorption rate of 97.5%, and the average absorption rate is more than 99% in the visible light band. By comparing with the standard solar spectrum (0.28–4.0 µm) under AM 1.5, the absorber can effectively absorb sunlight and coincide with the standard solar spectrum. Subsequently, we study the effects of different structures and materials on the performance of absorber. The absorber is insensitive to incident light angle and polarization angle, and can be used under natural environment. Finally, we further study the influence of the hole shape on the absorber. The relevant conclusions of the research exhibits better performance in the field of solar energy collection and conversion.