Quadruple-band polarization-insensitive wide-angle metamaterial absorber based on multi-layer structure

In this paper, a quadruple-band metamaterial absorber (MA) based on a multi-layer structure is presented. The resonators are metallic patches with different radii. In design of the unit cell, the patch with larger radius in the lower layer will not only present good resonance but also provide magnetic coupling with patch in the upper layer. The quadruple-band MA appears in four absorptive peak values at frequencies 10.71 GHz, 11.78 GHz, 13.01 GHz and 14.19 GHz, which has been experimentally proved. With geometrical parameters scaling, the quadruple-band MA presents good absorptivity at 1.85 THz, 2.46 THz, 3.08 THz and 3.84 THz. (C) 2015 Elsevier GmbH. All rights reserved.