Yang Qianru, Qin Linling, Cao Guoyang, Zhang Cheng, Li Xiaofeng
Opt Lett. 2018 Feb 15;43(4):639-642. doi: 10.1364/OL.43.000639.
We propose a graphene-coated photonic system with the excitation of Bloch surface waves (BSWs) for refractive index sensing. Through manipulation of the BSW resonance in the truncated photonic crystal under a Kretschmann configuration, the absorption in a graphene monolayer is significantly enhanced, assisted by the strong electromagnetic confinement of BSWs. The sharp and low reflectivity dip and the strong wave-environment interaction enable highly sensitive optical sensing. First-order perturbation theory and transfer-matrix calculation indicate that the system sensitivity is strongly related to the ratio of the electric field energy in the detection area, operation wavelength, and incident angle. Study shows that the wavelength sensitivity and figure of merit of the optimized system can reach 7023 nm/RIU and 196.44, respectively. More generalized BSW system configurations, e.g., aperiodic BSW design, are proposed for refractive index sensing application.
我们提出了一种用于折射率传感的、具有布洛赫表面波（BSW）激发的石墨烯涂层光子系统。通过在Kretschmann配置下对截断光子晶体中的BSW共振进行操控，在BSW的强电磁约束辅助下，石墨烯单层中的吸收显著增强。尖锐且低反射率的凹陷以及强烈的波与环境相互作用实现了高灵敏度的光学传感。一阶微扰理论和传输矩阵计算表明，系统灵敏度与检测区域中的电场能量、工作波长和入射角的比值密切相关。研究表明，优化系统的波长灵敏度和品质因数分别可达7023 nm/RIU和196.44。还提出了更通用的BSW系统配置，例如非周期BSW设计，用于折射率传感应用。
