A new tunable dual-band metamaterial absorber with wide-angle TE and TM polarization stability

In this research, a new tunable dual-band metamaterial absorber with wide-angle TE and TM polarization stability is proposed. The designed absorber exhibits two high absorption peaks at 5.1 and 8.5GHz with absorption peaks of 96 and 97%, respectively. The unit cell consists of a metallic background plane and two closed rings including two groups of T-shaped resonators, separated by a low-cost dielectric layer with thickness of 0.9mm. By tuning the distance between the T-shaped structures and closed ring, the corresponding two resonance frequencies can be effectively separated with high absorption over 95% while keeping the closed ring unchanged. The simulated results demonstrate that the designed absorber has good characteristics of high absorption rates, polarization-insensitiveness and wide angle of incident waves. A waveguide experiment is performed to verify the good agreement between the simulated and measured results.