中文摘要：

研究了在水溶液环境中亚波长金属狭缝阵列光学异常透射的折射率传感特性．采用严格的全矢量方法计算了狭缝阵列的透过率谱．建立了Fabry—Perot半解析模型，能够精确预言全矢量方法的计算结果．基于该模型给出的共振条件，提出并解释了当透射峰精确位于瑞利异常位置时，透射峰能达到最尖锐的状态，给出了设计狭缝阵列达到该状态的方法．设计得到的透过率谱峰值半高宽5A可达0．01nm，对应的溶液折射率测量不确定度δns达到2×10^-6RIU．系统地给出了阵列周期、狭缝宽度、入射角等参数对设计得到的传感灵敏度，δλ，δns，峰值透过率等的影响．

英文摘要：

The refractive index sensing properties of a period array of subwavelength metallic slits in water environment are investigated. The transmission spectra of the slit array are calculated with a rigorous fully-vectorial method. A simple semi-analytical Fabry-Perot model that can accurately reproduce the rigorous fully-vectorial data is built up. We find that the transmission peak becomes sharpest as it is exactly located at the Rayleigh anomaly position, which is explained based on the resonance condition derived from the model. The method to design the slit array to achieve this sharpest transmission peak is presented. The full width at half-maximum （SA） of the designed transmission peak can be as low as 0.01 nm, which corresponds to a refractive-index measurement uncertainty （δns） of 2 × 10^-6 RIU. The influences of array period, slit width and incident angle on the designed sensitivity, δλ, δns and peak transmittance of the sensor are systematically provided.