Quasi-bound states in the continuum (QBIC), with exceptionally high-Q factors and the local field enhancement effect, have found potential applications in matter sensing. Introducing the QBIC mechanism into terahertz (THz) metasurfaces can significantly enhance the interaction between incident THz waves and matter, providing a feasible platform for the detection of biochemical substances. Currently, most experimental studies on terahertz QBIC metasurfaces utilize metallic structures. By contrast, research on terahertz all-dielectric QBIC metasurfaces generally remains at the simulation stage due to the high fabrication process requirements, and transitioning to the experimental stage still poses many challenges. In this paper, a hollow-structured all-silicon metasurface supporting THz QBIC is proposed. The resonance of THz QBIC is excited via a simple hollow structure and observed in experiment. Simulations and experimental results demonstrated that the designed THz QBIC metasurface can achieve sensing of Auramine O. Notably, it is the first study, to our knowledge, to employ a metasurface to sense Auramine O. Additionally, the sensing performance maintains good stability under different humidity and temperature conditions. This study provides new references and insights for the design and implementation of THz QBIC, and also opens a new pathway for the detection of Auramine O.

中文翻译：

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中空结构全硅太赫兹超表面支持连续体中的准束缚态，用于基于折射率的金胺 O 浓度传感


连续体中的准束缚态（QBIC），具有极高的问因素和局部场增强效应，在物质传感中发现了潜在的应用。将QBIC机制引入太赫兹（THz）超表面可以显着增强入射太赫兹波与物质之间的相互作用，为生化物质的检测提供可行的平台。目前，大多数太赫兹 QBIC 超表面的实验研究都利用金属结构。相比之下，太赫兹全电介质QBIC超表面的研究由于制造工艺要求高，普遍停留在模拟阶段，过渡到实验阶段仍然面临许多挑战。本文提出了一种支持太赫兹QBIC的空心结构全硅超表面。太赫兹 QBIC 的共振是通过简单的中空结构激发的，并在实验中观察到。模拟和实验结果表明，所设计的太赫兹QBIC超表面可以实现Auramine O的传感。值得注意的是，据我们所知，这是第一个采用超表面来传感Auramine O的研究。此外，传感性能在不同湿度下保持良好的稳定性和温度条件。该研究为太赫兹QBIC的设计和实现提供了新的参考和见解，也为Auramine O的检测开辟了新途径。