Design a Multiplanar Metamaterial Solar Absorber Using COMSOL

Designing an all-planar metamaterial optical absorber that operates efficiently across a broad spectral range, from visible to infrared wavelengths, presents significant challenges due to the inherent difficulty of simultaneously achieving broadband coverage and high absorptivity using planar architectures.The core innovation of this study lies in the strategic use of cost-effective, earth-abundant materials to construct a high-performance optical absorber capable of covering the entire spectral range from 400 to 1980 nm. Unlike conventional approaches that often rely on expensive noble metals such as gold and silver, this work utilized more affordable alternativesnamely, copper (Cu), nickel (Ni), chromium (Cr), and titanium (Ti), and two different dielectric materials SiO 2 and MgF 2 -to design a multilayer, planar metamaterial structure.These metals were selected not only for their economic viability but also for their distinct optical and physical properties, which, when combined in an optimized configuration, contributed to superior absorption characteristics.The proposed absorber demonstrated an impressive ultra-broadband performance, with an absorptivity consistently exceeding 0.9 throughout the visible and nearinfrared range.Its average absorptivity reached as high as 0.979, and a peak absorptivity of 0.999 was recorded at certain wavelengths, effectively qualifying the device as a near-perfect absorber.Such high performance is rarely observed in planar structures composed solely of lowcost materials, underlining the novelty and practical significance of the design.