Plasmonic structures that support the spoof surface plasmon polariton (SSPP) mode can be tailored to achieve strong absorption of electromagnetic (EM) waves. In particular, the profile of an absorbing plasmonic structure (APS) plays an important role in realizing its wideband absorption performance. In this paper, we propose a method of optimizing the longitudinal profile of APS based on Genetic Algorithm (GA), with the aim of obtaining high-efficiency wideband absorption of EM waves. The APS unit cell is composed of a longitudinal array of metallic strips, the length profile of which can be optimized to improve k-matching between free-space waves and SSPPs and meanwhile to customize absorption at each frequency within a wide band. Our investigation shows that non-linear variation of the strip lengths will make better k-matching and wideband absorption. As an example, a wideband APS is demonstrated using this method. The simulated and measured results show that the absorbance is higher than 90% in 10–30 GHz, which convincingly verifies the effectiveness of this method. This method provides an efficient approach to the design of radar absorbing structures and can also be extended to optimized design of other metamaterials.

可以定制支持欺骗性表面等离振子极化（SSPP）模式的等离激元结构，以实现对电磁（EM）波的强吸收。特别地，吸收性等离子体结构（APS）的轮廓在实现其宽带吸收性能中起重要作用。本文提出了一种基于遗传算法（GA）的优化APS纵剖面的方法，旨在获得EM波的高效宽带吸收。APS晶胞由金属条的纵向阵列组成，其长度分布可以优化以改善ķ-在自由空间波和SSPP之间进行匹配，同时定制宽带内每个频率的吸收。我们的研究表明，带材长度的非线性变化会更好ķ匹配和宽带吸收。例如，使用此方法演示了宽带APS。仿真和测量结果表明，在10–30 GHz中，吸光度高于90％，这令人信服地证明了该方法的有效性。该方法为雷达吸收结构的设计提供了一种有效的方法，并且还可以扩展到其他超材料的优化设计。