A flexible lightweight graphene-based all-dielectric metamaterial for broadband microwave absorption

To meet the demanding requirements of practical microwave absorbers, such as broadband absorption, considerations must encompass thickness, flexibility, surface density, and manufacturing feasibility. However, absorbers that effectively address all of these aspects are currently scarce. This study introduces a novel graphene-based all-dielectric metamaterial absorber (ADMMA) featuring a trap-like structure, inspired by impedance alternation strategy. Leveraging the dielectric dispersion properties of graphene composites, this ADMMA strategically manipulates the effects of Spoof Surface Plasmon Polaritons, standing wave resonance and half-wave dipole resonance, allocating them to distinct frequency bands, thus achieving a thin-layer broadband absorber. Simulation results demonstrate that, under vertical incidence, the ADMMA achieves a -10 dB bandwidth from 8.1 to 23.1 GHz. A 3 mm-thick sample, with a surface density of merely 2.85 Kg m-2, is fabricated using a straightforward process, and reflectance test results closely align with simulation outcomes. Furthermore, it exhibits robust stability under oblique incidences for both TE and TM modes. This innovative approach effectively reduces surface density without compromising absorption performances, emphasizing the potential of the ADMMA for practical applications.