Design and optimization of a flexible water-based microwave absorbing metamaterial

Water is one of the most promising dielectric materials for microwave absorption due to its superior broadband dielectric loss. Inspired by the mechanism of traditional metamaterials, we have designed a water-based dielectric loss microwave absorber based on 3D-printing technology. Through stepwise structural optimization, the fabricated flexible water-based metamaterial experimentally demonstrated an ultra-broadband absorption in the frequency range 5.9–25.6 GHz with a thickness of 4 mm. Meanwhile, its angular tolerance also demonstrated wide-angle absorption capability. All these properties make it suitable for practical electromagnetic applications such as microwave radiation protection technology and microwave shielding boxes.