A Three-dimensional Resistive Metamaterial with Extremely Broadband Absorption

A three-dimensional broadband typical meta-material absorber (3D BMA) is designed through a three-layer sandwich structure in which the dielectric layer and the top resistive film layer stand upright on the bottom metallic plate. Its absorption performance is optimized and studied. Numerical results show that the absorption of the 3D BMA is more than 90% in the range of 8.3-40GHz under normal incidence. When the incident angle changes from 0° to 60°, the absorption is more than 90% in the range of 8.2-25GHz , except for two dips at 21.2GHz and 22.5GHz with the angles of 45° and 60°, respectively. Thus, this may provide a distinct guideline for fabricating broadband metamaterial absorbers.