基于二维孔阵列光栅耦合激发布洛赫表面波的高灵敏度生物传感

Two-Dimensional Hole-Array Grating-Coupling-Based Excitation of Bloch Surface Waves for Highly Sensitive Biosensing.

作者信息

Ge Daohan, Shi Jianpei, Rezk Ahmed, Ma Chao, Zhang Liqiang, Yang Ping, Zhu Shining

机构信息

School of Mechanical Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China.

National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing, 210093, People's Republic of China.

出版信息

Nanoscale Res Lett. 2019 Oct 10;14(1):319. doi: 10.1186/s11671-019-3159-8.

DOI:10.1186/s11671-019-3159-8

PMID:31599355

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6787138/

Abstract

In this study, a surface diffraction two-dimensional (2D) grating structure was placed on the topmost layer of distributed Bragg reflectors (DBRs) for biosensing. Bloch surface wave (BSW) resonance was realized by coupling a 2D subwavelength hole-array grating and could be excited at different locations: the surface of 2D-grating layer or the inter-face between the DBR and bio-solution. Material losses in the multilayer dielectric were measured to test the robustness of this scheme. Both the surface diffraction-grating BSW (DG-BSW) and the alternative guided grating-coupled BSW (GC-BSW) configuration showed markedly enhanced angular sensitivity compared to conventional prism-coupled schematics. Exciting these modes using a grating-coupling technique appears to yield different extreme sensitivity modes with a maximum of 1190°/RIU for DG-BSW and 2255°/RIU for GC-BSW. Refractive index sensors with a high figure of merit may be realized via such compact configurations.

摘要

在本研究中，为了进行生物传感，在分布式布拉格反射器（DBR）的最顶层放置了一种表面衍射二维（2D）光栅结构。通过耦合二维亚波长孔阵列光栅实现了布洛赫表面波（BSW）共振，并且可以在不同位置激发：二维光栅层的表面或DBR与生物溶液之间的界面。测量了多层介质中的材料损耗以测试该方案的稳健性。与传统的棱镜耦合原理图相比，表面衍射光栅BSW（DG-BSW）和替代的引导光栅耦合BSW（GC-BSW）配置均显示出明显增强的角度灵敏度。使用光栅耦合技术激发这些模式似乎会产生不同的极端灵敏度模式，DG-BSW的最大值为1190°/RIU，GC-BSW的最大值为2255°/RIU。通过这种紧凑的配置可以实现具有高优值的折射率传感器。