Multi-Spectral Metasurface With High Optical Transparency, Low Infrared Surface Emissivity, And Wideband Microwave Absorption

In this article, we propose the design of a multispectral metasurface (MSM), which can simultaneously achieve quite good optical transparency, low infrared (IR) emissivity, and wideband microwave absorption. To this end, optically transparent materials were used in the MSM design, including indium tin oxide, polyethylene terephthalate, and polymethyl methacrylate. The MSM is composed of three functional layers: a frequency-selective surface (FSS) on the top, a resistively absorbing layer in the middle and a complete conducting sheet at the bottom. Because of large occupation ratio of conducting area and the low-pass property of the FSS, electromagnetic waves are allowed to penetrate through it into the middle absorbing layer, simultaneously with low surface IR emissivity. A prototype was designed, fabricated, and measured. Both the simulation and experiment results show that the MSM can achieve strong absorption of > 90% in 12.03-29.43 GHz and low IR emissivity of about 0.3 in 3.0-14.0 mu m simultaneously. Moreover, the average optical transparency is higher than 90%. Because of the excellent multispectral compatibility, the MSM may find applications in electromagnetic protection, stealth technologies, etc.