An Ultrathin Compact Polarization-Insensitive Hepta-Band Absorber

In this paper, an ultrathin, compact, hepta-band metamaterial absorber (MMA) is proposed for the first time. The MMA absorber is realized integrating two multiband MMA structures nested one inside the other. The novelty of the proposed structure lies in its four-fold symmetric nature which allows it to be polarization-insensitive absorber. The absorption mechanism at the seven resonating peaks has been explained with the help of simulated surface current distribution plots. The proposed work is expected to find its applications in various domains such as radar absorbing material (RAM), remote sensing, electromagnetic interference (EMI)/electromagnetic compatibility (EMC), and thermal imaging.