Wang Jing, Tan Peng, Li Shuai, Wang Guanchao, Guo Wenpeng, Zhou Zhongxiang, Tian Hao
Opt Express. 2021 May 10;29(10):15541-15550. doi: 10.1364/OE.425849.
A tunable polarization-independent plasmon-induced transparency (PIT) metasurface based on connected half-ring and split-ring resonators is proposed to working in the terahertz band. We analyze the PIT effect in metasurfaces comprising of ring resonator and split ring resonator. Due to the magnetic attenuation caused by the reverse current between the two resonators, the relative position of the ring resonator and the split-ring resonator greatly affects the strength of the PIT effect. Magnetic attenuation weakens the dark mode of the split ring resonator. Through simulation and experiment, it is found that connecting the ring resonator and split-ring resonator can avoid magnetic attenuation and achieve a stronger PIT window. Furthermore, the fourfold rotation structure of the connected half-ring and split-ring resonator on silicon substrate achieves an optically controlled polarization-independent PIT effect. The design would provide significant guidance in multifunctional active devices, such as modulators and switches in terahertz communication.
提出了一种基于相连半环和开口环谐振器的可调谐偏振无关等离子体诱导透明（PIT）超表面，用于太赫兹波段工作。我们分析了由环形谐振器和开口环谐振器组成的超表面中的PIT效应。由于两个谐振器之间的反向电流引起的磁衰减，环形谐振器和开口环谐振器的相对位置对PIT效应的强度有很大影响。磁衰减削弱了开口环谐振器的暗模式。通过仿真和实验发现，连接环形谐振器和开口环谐振器可以避免磁衰减并实现更强的PIT窗口。此外，硅基片上相连半环和开口环谐振器的四重旋转结构实现了光控偏振无关PIT效应。该设计将为多功能有源器件，如太赫兹通信中的调制器和开关，提供重要指导。
