Opt Express. 2022 Sep 12;30(19):34034-34042. doi: 10.1364/OE.464346.
Toroidal dipole resonance can significantly reduce radiation loss of materials, potentially improving sensor sensitivity. Generally, toroidal dipole response is suppressed by electric and magnetic dipoles in natural materials, making it difficult to observe experimentally. However, as 2D metamaterials, metasurfaces can weaken the electric and magnetic dipole, enhancing toroidal dipole response. Here, we propose a new graphene-integrated toroidal resonance metasurface as an ultra-sensitive chemical sensor, capable of qualitative detection of chlorothalonil in the terahertz region, down to a detection limit of 100 pg/mL. Our results demonstrate graphene-integrated toroidal resonance metasurfaces as a promising basis for ultra-sensitive, qualitative detection in chemical and biological sensing.
环形偶极子共振可以显著降低材料的辐射损耗，从而提高传感器的灵敏度。通常情况下，环形偶极子响应会被天然材料中的电偶极子和磁偶极子抑制，这使得在实验中很难观察到。然而，作为二维超材料，超表面可以减弱电偶极子和磁偶极子，从而增强环形偶极子的响应。在这里，我们提出了一种新的石墨烯集成环形共振超表面作为超灵敏化学传感器，能够在太赫兹区域对百菌清进行定性检测，检测限低至 100pg/ml。我们的结果表明，石墨烯集成环形共振超表面是化学和生物传感中超灵敏、定性检测的有前途的基础。
