Plasmonic Fano resonances, which result from the interaction between two plasmon modes in subwavelength nanostructures, provide a unique way to realize promising applications in light manipulation technology. Here, we investigate the infrared plasmonic Fano resonances of subwavelength periodic hole arrays with different geometric configurations in a metallic film containing Z-shaped hole arrays, cross-shaped aperture arrays, and gammadion-shaped hole arrays (GSHAs). Specifically, the infrared plasmonic Fano resonance in the GSHA structure, without considering rotational symmetry breaking, can be interpreted as stemming from the coupling between the bonding and antibonding localized surface plasmon resonance modes. By considering the rotational symmetry breaking in the GSHA structure, it is possible to actualize plasmonic double- and triple-Fano resonances in the near-infrared or mid-infrared region. Moreover, the plasmonic double- and triple-Fano resonances between the first- and second-NIR optical windows, as well as in the mid-infrared region can be controlled by appropriately regulating the related length of the arms in the GSHA structure. Our results show that infrared plasmonic Fano resonances might pave the way for the exploration of applications in optical communications and information processing.

由亚波长纳米结构中两个等离振子模式之间的相互作用产生的等离子Fano共振提供了一种独特的方式来实现光操纵技术中有希望的应用。在这里，我们研究了包含Z形孔阵列，十字形孔阵列和gammadion形孔阵列（GSHAs）的金属膜中具有不同几何构型的亚波长周期孔阵列的红外等离子体激元Fano共振。具体而言，在不考虑旋转对称破坏的情况下，GSHA结构中的红外等离子体Fano共振可以解释为源于键合和反键合局部表面等离子体共振模式之间的耦合。考虑到GSHA结构中的旋转对称破坏，有可能在近红外或中红外区域实现等离子双-和三-法诺共振。而且，可以通过适当地调节GSHA结构中臂的相关长度来控制第一和第二NIR光学窗口之间以及中红外区域中的等离子双和三Fano共振。我们的结果表明，红外等离子体Fano共振可能为光通信和信息处理应用的探索铺平道路。