Design of a broadband infrared metamaterial absorber

A broadband infrared metamaterial absorber based on the combination of four different resonators is presented and numerically examined. There are two resonant layers with different dielectrics in the absorber. The simulated absorptivity is beyond 90% for 8-12 μm wavelength and the absorber is polarization independent. We studied the absorbent mechanism by the distribution of magnetic fields and energy dissipation in the absorber. The absorptivity stays quasi constant for the incident angle up to 25°. Further simulation shows that we can change the absorption band through the optimization of the geometrical parameters.