Dual band metamaterial absorber: Combination of plasmon and Mie resonances

Abstract

A dual band metamaterial absorber composed of dielectric and metallic atoms with high symmetry was numerically designed and experimentally verified. Due to simultaneously generated electric and magnetic resonances of both plasmon and Mie resonators, two absorption peaks with near unity absorptivity were obtained at 9.45 and 9.80 GHz. The loss of the electromagnetic wave at the first resonance frequency was mainly caused by ohmic loss based on plasmon resonance. For the second absorption peak resonance frequency, the incident wave was trapped inside the dielectric cube and the main loss of the electromagnetic wave was caused by dielectric loss based on Mie resonance. Most of the proposed dual band metamaterial absorbers were sensitive to the polarization direction hindering its potential applications in scientific and technological areas. Combing both plasmon and Mie resonances provides a new and simple way to build dual band isotropic metamaterial perfect absorbers eliminating polarization effect.