Design and Evaluation of Ultra-broadband Metamaterial Absorber for Energy Harvesting Applications

Abstract

A perfect metamaterial absorber (MMA) is designed and evaluated numerically for solar energy harvesting applications. A dielectric layer separates the top structured metallic plane and the bottom ground metallic plane that make up the MMA. The MMA structure is primarily presented in the range of 100-1000 THz, which corresponds to 3000-300 nm in wavelength, for the efficient utilization of solar energy. The results obtained in the band 441-998 THz correspond to a visible and ultraviolet wavelength range of 680-300 nm. It has achieved a maximum absorption rate of 99.9% at 700 THz and 99% between 500 and 800 THz, respectively. In the desired frequency bands, the structure has achieved polarization and angle-resolved behavior. The MMA-based absorber has a high absorption rate of over 90% in the broadest visible (400-700 nm) and UV (100-300 nm) spectra. Also shown are the absorption characteristics of the MMA-based solar cell in the infrared (IR) region. The band 345-440 THz, corresponding to 870-690 nm, has 75% absorption. The other IR band (240-345 THz), which corresponds to 1250-880 nm, has achieved absorption of nearly 50%. So it can be utilized for the entire visible solar spectrum, including infrared to ultraviolet. If the proposed MMA structure were equipped with the appropriate electrical circuitry, it could be utilized for solar energyharvesting.