▎ 摘　　要

Here, we present an ultralight multilayered graphene-based metasurface for suppressing specular reflection. With the help of a joint optimization method, dual low-reflection mechanisms including absorption and random diffusion are realized within the same structure, resulting in a remarkable decrease in the backward reflected energy in an ultrabroadband range of 7.5 to 43 GHz (a relative bandwidth of 140.6%). Experiments demonstrate that our design with a thickness of approximately 3.27 mm can maintain excellent antireflection performance over a wide angle range of 0 to 45 degrees for both TE and TM waves. Additionally, as a result of adopting low-density substrates (polyethylene terephthalate and polymethylacrylimide foam) and multilayered graphene films, the proposed metasurface shows the advantage of ultralight weight, thus opening an avenue for a number of engineering applications such as electromagnetic shielding, information security, and electromagnetic compatibility technology. In addition, owing to the natural characteristics (corrosion resistance, bending resistance, etc.) of multilayered graphene films, the proposed metasurface shows enormous potential in some particular application scenarios with harsh conditions.