Mechanically flexible symmetric metamaterial absorber in UV to visible wavelength for solar energy and optical window application

This work presents a novel metamaterial absorber (MTMA) based on the SiO₂–Ni–SiO₂–Ni layer that operates in the Ultraviolet (UV) and visible spectrum for solar energy cell and optical window applications. The simulation is conducted for the UV range of 100 nm to 133 nm and the visible region of 348 nm to 652 nm with a near-perfect high absorption and peak absorbance of 99.9% at 464.6 nm and 99.6% at 105.0 nm. The absorber is simulated with TE and TM polarized modes, but no significant changes are observed since its absorbance is constant up to 60°. MTMA's effectiveness is also determined by the Polarization Conversion Ratio (PCR), which is nearly zero. The mechanical bending impact shows a wideband absorbance between −30° and 30°. The proposed MTMA has a fractional bandwidth of 29.00% and 60.77%, with absolute bandwidths of 33.88 nm and 304.14 nm, in the UV and visible spectrum, respectively. The absorption under the AM1.5 solar spectrum is observed by varying the ground and substrate layer thickness. The findings of short-circuit current density, open-circuit voltage (V_oc), high conversion efficiency, and fill factor make it an ideal absorber for optical applications like sensors, light detectors, imaging, nano solar cells, and optical windows.