Wide-angle electromagnetic wave absorption via multilayer metamaterial structures

Abstract This work proposes a facile wide incident angle metamaterial absorber (MA) using a multilayer structure. The suggested MA consists of two ring-shaped resonant layers. Under normal incidence, the proposed MPA exhibits an absorption peak at 4.31 GHz with an absorption of 98.9%. The impact of incident angle on absorption characteristics of our MA is investigated experimentally for both transverse electric (TE) and transverse magnetic (TM) modes. In the TE mode, at an incident angle of 70 degrees, the MPA exhibits two absorption peaks at 4.23 and 4.39 GHz with absorptions of 88.7% and 97.5%, respectively. In the TM mode, the absorption intensity of the proposed MA is maintained at 90% with an incident angle of up to 50 degrees and descended to below 90% at an incident angle of 70 degrees. In addition, the role of multilayer structure on the incident angle broadening of MA is also discussed and clarified.