Polarization and Incidence Angle Independent Low-Profile Wideband Metamaterial Electromagnetic Absorber Using Indium Tin Oxide (ITO) Film

Abstract

We use indium tin oxide (ITO), one of the representative resistive materials, for the implementation of a metamaterial electromagnetic (EM) absorber with a high absorbance in a wide frequency range. Highly symmetrical split ring resonators made of ITO film are deposited on the polyethylene terephthalate with transparent and flexible features, and such a configuration causes the proposed absorber to be insensitive to polarization and incidence angles. The proposed absorber, with a profile of only 0.171λ, exhibits a wideband absorbance of 7.2 GHz to 27 GHz, with a 90% absorption criterion. A prototype is built, and all the computed expectations from the full-wave EM simulations in this work are verified experimentally.