Opt Lett. 2019 Mar 15;44(6):1444-1447. doi: 10.1364/OL.44.001444.
The double toroidal spoof localized surface plasmons (LSPs) on combined split ring resonators (SRRs) are proposed and experimentally demonstrated at microwave frequencies. Based on conventional printed circuit board techniques on a dielectric substrate, the designed metamaterial clearly shows two toroidal spoof LSP resonances. Two toroidal spoof LSP resonances are excited due to the conductive coupling and magneto-inductive coupling, respectively. Both numerical simulations and experiments are in good agreement. It is shown that the toroidal spoof LSP resonance is sensitivie to the local dielectric environments. Hence, the combined SRRs may be used as plasmonic sensors and find potential applications in the microwave and terahertz frequencies.
双环形超表面等离激元（LSPs）在组合型开口环谐振器（SRRs）上的应用在微波频率下得到了实验验证。基于介质衬底上的传统印刷电路板技术，所设计的超材料清晰地显示出两个环形超表面等离激元共振。两个环形超表面等离激元共振分别是由于传导耦合和磁电耦合而被激发的。数值模拟和实验结果吻合较好。实验结果表明，环形超表面等离激元共振对局部介电环境很敏感。因此，组合型开口环谐振器可以作为等离子体传感器，在微波和太赫兹频段有潜在的应用。
