Most of terahertz lattice-induced transparency behaviors are investigated under the lattice modes matching the plasmonic modes. Alternatively, we propose terahertz polarization-insensitive array-induced transparency effect due to diffractive coupling in between two collective eigenmodes of meta-atoms on sublattice-sites in the metasurface of embedded square lattice. Aforementioned two collective eigenmodes destructively interfere each other so as to induce a transparency window in frequency spectrum. A large positive group delay (30 ps) is foreseen in the vicinity of the induced transparency window (0.37 THz), where the electric susceptibility is zero. Our finding manifests a new design of terahertz polarization-insensitive slow light device.

中文翻译：

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偏振不敏感的太赫兹阵列诱导的嵌入式方形晶格衍射耦合超表面的透明性

在与等离子体模式匹配的晶格模式下，研究了大多数太赫兹晶格诱导的透明行为。或者，由于嵌入的方格亚表面的亚晶格位点上，亚原子的两个集体本征模式之间存在衍射耦合，因此我们提出了太赫兹偏振不敏感的阵列诱导的透明效应。上述两个集体本征模式相消地相互干扰，从而在频谱上产生了透明窗口。在电导率为零的感应透明窗（0.37 THz）附近，预计会有较大的正群延迟（30 ps）。我们的发现表明了对太赫兹偏振不敏感的慢光器件的新设计。