Realization of broadband and independent polarization metamaterial perfect absorber based on the third-order resonance

Abstract

Since the first observation of the fascinating absorption property, metamaterials have been become a scientific spotlight. A distinctive interest has been given to metamaterial absorber (MA) with a broad operating band, which are more useful for future applications. In this report, we studied numerically and experimentally the electromagnetic properties of perfect MAs using ring-shaped structures at microwave frequencies. By creating a magnetic resonance, the ring structure confines electromagnetic energy at the first- and third-order resonances. And then, we leveraged the super-cell structures, which consist of different rings in one unit cell to obtain broadband absorption. The results showed that the absorption band of MA is broaden from 1.3 to 2.17 GHz when the number of rings in the unit cell increases from four to nine-rings. The experiment results are in good agreement with the simulation ones. Finally, by applying the same model, we simulated the MA working at THz frequency. Especially, all GHz- and THz-MAs are optimized by the third-order magnetic resonance, which occurs at a frequency three times higher than the fundamental resonance one.