Compact penta-band metamaterial absorber: achieving polarization insensitivity and optimized bandwidth performance

This article describes narrow penta-band metamaterial absorbers that are polarization-insensitive for multi-band frequency applications. The present absorber cell is made up of four resonators. These resonators are imprinted on the top section of double-sided epoxy glass FR-4 covered with copper and the depth of FR-4 is 1.6 mm. The presented absorber design produces five separate absorption peaks specifically, 92.7% (peak-1) at 2.7 GHz, 94% (peak-2) at 6.5 GHz, 93% (peak-3) at 9.4 GHz, 98% (peak-4) at 13.3 GHz and 98% (peak-5) at 15.5 GHz, respectively in the process of normal occurrence. Additionally, the arrangement of the absorber pattern provides above 90% absorption peaks at all angles of incidence (before \({60}^\circ\) ${60}^{\circ }$ ) in equally transversal-electric and transversal-magnetic polarisation conditions. The ongoing development and exploration of metamaterial design hold great promise for achieving unprecedented control over electromagnetic wave absorption, thus opening up exciting opportunities for a wide range of practical applications.