Lightweight conformal design of optically transparent and broadband microwave absorbing metamaterial

Conventional absorbing materials struggle to simultaneously achieve broadband high-efficiency microwave absorption, high optical transparency, low weight, and conformal capabilities. To overcome these limitations, this paper presents a transparent absorbing metamaterial (TAM) consisting of indium tin oxide (ITO) resistive films compounded with a thin-walled honeycomb backbone. A key innovation is the use of additive manufacturing to create a transparent honeycomb dielectric layer whose tailorable Poisson’s ratio enables precise conformal adaptation to complex curved surfaces. Experimental and simulation results consistently demonstrate that the TAM achieves over 90% absorptivity across an ultra-broadband frequency range of 5.6–19.2 GHz. Concurrently, it maintains a high visible transmittance of 82.59% and an ultralow areal density of 1.11 kg/m2. The TAM also exhibits robust absorption stability against wide-angle and polarization-diverse microwave incidence. The potential of this metamaterial is further demonstrated through its successful integration with solar cell arrays, highlighting its suitability for advanced optoelectronic systems.