Multi-band polarization-insensitive metamaterial absorber based on Chinese ancient coin-shaped structures

In this paper, the design, simulation, fabrication, and measurement of the five-band metamaterial absorber (MMA) based on Chinese ancient coin-shaped structure are proposed. Simulation results show that the proposed absorber has five distinctive absorption peaks at frequencies of 2.538 GHz, 7.092 GHz, 9.702 GHz, 13.302 GHz, and 15.588 GHz with the absorptivity of 0.99, 0.99, 0.99, 0.98, and 0.99, respectively. Experiment results matches well with the simulation. Both simulation and experiment results exhibit that the MMA sample is polarization insensitive for transverse electric and transverse magnetic incident wave. It also shows that high absorption for wide angle of incidence is up to 60 degrees. Finally, the current distribution for the MMA is presented to gain an insight into the physics behind the multiple absorption mechanism. The five-band absorber is promising candidates as absorbing elements in scientific and technical applications because of its multiband absorption, polarization insensitive, and wide angle incidence. (C) 2014 AIP Publishing LLC.