Wang Sheng Lei, Xiao Jun Jun, Zhang Qiang, Zhang Xiao Ming
Opt Express. 2014 Oct 6;22(20):24358-66. doi: 10.1364/OE.22.024358.
Stereometamaerials can fully utilize the 3D degrees of freedom to exploit the coupling and hybridization between multiple split ring resonators (SRRs), enabling more extraordinary resonances and properties over their planar counterparts. Here we propose and numerically study a kind of structure based on connected SRRs sharing their gap in a rotational fashion. It is shown that there are three typical resonance modes in such cage-like SRR (C-SRR) stereometamaterial in the communication and near infrared range. In the order of increasing energy, these modes can be essentially ascribed to magnetic torodial dipole, magnetic dipole, and a mixture of electric-dipole and magnetic toroidal dipole. We show that the latter two are derived from the second-order mode in the corresponding individual SRR, while the first one from the fundamental one. The highest energy mode remains relatively "dark" in an individual C-SRR due to the high-order feature and the rotational symmetry. However, they are all easily excitable in a C-SRR array, offering multiband filtering functionality.
立体超材料可以充分利用三维自由度来开发多个分裂环谐振器（SRR）之间的耦合和杂化，从而比其平面同类材料具有更多非凡的谐振和特性。在此，我们提出并通过数值研究了一种基于以旋转方式共享间隙的连接SRR的结构。结果表明，在通信和近红外范围内，这种笼状SRR（C-SRR）立体超材料存在三种典型的谐振模式。按能量增加的顺序，这些模式基本上可归因于磁环偶极子、磁偶极子以及电偶极子和磁环偶极子的混合。我们表明，后两种模式源自相应单个SRR中的二阶模式，而第一种模式源自基模。由于高阶特性和旋转对称性，最高能量模式在单个C-SRR中相对“暗”。然而，它们在C-SRR阵列中都很容易被激发，从而提供多波段滤波功能。
