Visible-infrared dual-spectral window metamaterial compatible with excellent electromagnetic shielding and high X-band absorption

Aiming at the requirements of multi-spectral transparency, electromagnetic (EM) shielding and radar stealth for window materials in visible-infrared (IR) integrated optoelectronic systems, this paper proposes a double-layer indium tin oxide (ITO) micro-nano structure metamaterial based on a ZnS substrate, which realizes the efficient coupling of "dual - spectral transparency - EM shielding - radar stealth". Through the periodic collaborative design of the bottom orthogonal grid network and the upper concentric square ring patches, while ensuring high transmittance in the visible light (380-780 nm) and IR (2-10 μm) bands, the EM shielding efficiency (SE) in the 100 MHz to 1 GHz frequency band is achieved to be more than 20 dB, and the absorption rate in the X-band (8-12 GHz) is more than 90%. Theoretical modeling and simulation reveal the composite action mechanism of "grid equivalent admittance shielding-resonant cavity energy dissipation", and magnetron sputtering and photolithography techniques are adopted to achieve millimeter-scale microstructure fabrication. Experimental results show that this metamaterial breaks through the balance limitations among light transmittance, SE, and radar stealth performance of traditional transparent shielding materials, providing an integrated solution for the protection of optoelectronic systems in complex EM environments.