Li Liye, Wu Wengang
National Key Laboratory of Advanced Micro and Nano Manufacture Technology, Beijing, 100871, PR China.
School of Integrated Circuits, Peking University, Beijing, 100871, PR China.
Microsyst Nanoeng. 2025 Jan 8;11(1):1. doi: 10.1038/s41378-024-00848-5.
The localized surface plasmon resonance metasurface is a research hotspot in the sensing field since it can enhance the light-matter interaction in the nanoscale, but the wavelength sensitivity is far from comparable with that of prism-coupled surface plasmon polariton (SPP). Herein, we propose and demonstrate an ultrasensitive angular interrogation sensor based on the transverse electric mode surface lattice resonance (SLR) mechanism in an all-metal metasurface. In theory, we derive the sensitivity function in detail and emphasize the refraction effect at the air-solution interface, which influences the SLR position and improves the sensitivity performance greatly in the wide-angle. In the measurement, a broadband light source substitutes the single-wavelength laser generally used in traditional angular sensing, and the measured SLR wavelength of broadband illuminant at normal incidence is defined as the single wavelength, avoiding the sensitivity loss from the large angle. The experimental sensitivity can reach 4304.35°/RIU, promoting an order of magnitude compared to those of SPP-sensors. This research provides a novel theory as well as the corresponding crucial approach to achieving ultrasensitive angular sensing.
局域表面等离子体共振超表面是传感领域的一个研究热点，因为它可以增强纳米尺度下的光与物质相互作用，但其波长灵敏度远不及棱镜耦合表面等离子体激元（SPP）。在此，我们提出并展示了一种基于全金属超表面中横向电模表面晶格共振（SLR）机制的超灵敏角度探测传感器。理论上，我们详细推导了灵敏度函数，并强调了空气 - 溶液界面处的折射效应，该效应影响SLR位置并在广角范围内极大地提高了灵敏度性能。在测量中，宽带光源替代了传统角度传感中通常使用的单波长激光，并且将宽带照明光垂直入射时测得的SLR波长定义为单一波长，避免了大角度导致的灵敏度损失。实验灵敏度可达4304.35°/RIU，比SPP传感器提高了一个数量级。本研究为实现超灵敏角度传感提供了一种新颖的理论以及相应的关键方法。
