Huygens' Metasurface Based on Induced Magnetism: Enhance the Microwave Absorption Performance of Magnetic Coating

Despite great efforts in material design and modification, there are still obstacles to improve the effective microwave absorption, which hinders the development of stealth materials. By introducing a magnetically induced Huygens' metasurface with Fibonacci spiral meta-atom, a hierarchical absorber with carbonyl iron particle coating is designed and prepared, of which the total effective absorption bandwidth (EAB, reflection loss <=-10 dB) amazingly reaches 9.41 GHz, exceeding 199% of the original coatings', and the absorption peak value declines from -15.91 to -32.12 dB. The overall thickness of the absorber is 7 mm, only 0.17 over the minimum thickness dictated by the causality limit. A conceptual basis for the proposed design is provided, that is, the balance of effective surface current and magnetic current induced simultaneously will enhance the electromagnetic (EM) wave transmission, which contributes to broadening the absorption bandwidth with promising impedance matching. The system is validated numerically and experimentally, suggesting a novel route to obtain high-performance microwave absorption materials for the EM stealth technology.

Automated summary

In this study, a high-performance microwave absorption material is successfully designed and prepared by introducing a magnetically induced Huygens' metasurface with Fibonacci spiral meta-atom. The absorber exhibits a total absorption bandwidth of 9.41 GHz and a significant decrease in absorption peak value. The enhancement of electromagnetic wave transmission and the broadening of absorption bandwidth are achieved by balancing effective surface current and magnetic current induced simultaneously.