Kim Yongjune, Park Pyoungwon, Jo Jeongdai, Lee Joonsik, Jeong Leekyo, Shin Jonghwa, Lee Jeong-Hae, Lee Hak-Joo
Metamaterial Electronic Device Research Center, Hongik University, Seoul, 04066, South Korea.
Center for Advanced Meta-Materials, Daejeon, 34103, South Korea.
Sci Rep. 2021 Nov 29;11(1):23045. doi: 10.1038/s41598-021-02303-1.
An ultrawideband electromagnetic metamaterial absorber is proposed that consists of double-layer metapatterns optimally designed by the genetic algorithm and printed using carbon paste. By setting the sheet resistance of the intermediate carbon metapattern to a half of that of the top one, it is possible to find an optimal intermediate metapattern that reflects and absorbs the EM wave simultaneously. By adding an absorption resonance via a constructive interference at the top metapattern induced by the reflection from the intermediate one, an ultrawideband absorption can be achieved without increasing the number of layers. Moreover, it is found that the metapatterns support the surface plasmon polaritons which can supply an additional absorption resonance as well as boost the absorption in a broad bandwidth. Based on the simulation, the [Formula: see text] absorption bandwidth is confirmed from 6.3 to 30.1 GHz of which the fractional bandwidth is 130.77[Formula: see text] for the normal incidence. The accuracy is verified via measurements well matched with the simulations. The proposed metamaterial absorber could not only break though the conventional concept that the number of layers should be increased to extend the bandwidth but also provide a powerful solution to realize a low-profile, lightweight, and low cost electromagnetic absorber.
提出了一种超宽带电磁超材料吸收体，它由通过遗传算法优化设计并使用碳糊印刷的双层金属图案组成。通过将中间碳金属图案的薄层电阻设置为顶部图案的一半，可以找到一种既能反射又能吸收电磁波的最佳中间金属图案。通过中间图案反射在顶部图案处产生相长干涉来增加吸收共振，无需增加层数即可实现超宽带吸收。此外，发现金属图案支持表面等离激元极化激元，其可以提供额外的吸收共振并在宽带宽内增强吸收。基于模拟，对于垂直入射，确认了从6.3到30.1 GHz的吸收率带宽，其中分数带宽为130.77%。通过与模拟结果良好匹配的测量验证了精度。所提出的超材料吸收体不仅可以突破增加层数来扩展带宽的传统概念，还可以为实现低剖面、轻质和低成本的电磁吸收体提供有力的解决方案。
