Dual Band Perfect Absorber based on Metamaterials

Perfect absorption can be achieved by using the extraordinary properties of metamaterials. The impedance of the metamaterial and the free space can be matched by adjusting the geometrical parameters of the resonator with the type and the thicknesses of the materials. At these parameter values, where impedance matching is achieved, 100% absorption at the resonance wavelength can be obtained. In this study, it is shown theoretically and experimentally that double-band perfect absorption can be achieved with a simple U-shaped antenna. The double-band perfect absorber proposed in this study can be used in bio-sensing and detector applications with its narrow-band structure.