光纤表面等离子体共振传感器具有体积小、抗电磁干扰,可以实现在线实时远距离检测的优点.为提高传感器的性能,建立了侧边抛磨光纤表面等离子体共振传感的物理模型,分别研究了侧边抛磨光纤的剩余厚度、银膜层的厚度对传感器的灵敏度、共振峰的深度和半高全宽等的影响.结果表明:光纤剩余厚度越小,表面等离子体共振现象越强;随银膜层的厚度增大,共振峰的宽度变宽,而传感器的灵敏度呈现非单调变化.通过综合表面等离子体共振传感器的折射率传感灵敏度和共振峰半高全宽,提出了质量因数作为传感器的优化指标,并最终得到最优化的设计方案为光纤剩余厚度为66.5 μm,银膜的厚度为50 nm,此时质量因数达到98.67.

Fiber-coupling surface Plasmon resonance sensor has attractive advantages of information transmission such as small volume,anti-electric magnetic field interference,and online real-time remote detection.In order to improve the performance of the sensor,the effect of the residual fiber thickness and the silver film thickness to the sensitivity of the sensor and the depth of the resonance peaks and full width ar half maximum(FWHM) are analyzed respectively.The results show that the increasing fiber residual thickness weakens the SPR phenomenon,and that the increasing silver film thickness widens the resonance peak,while the sensitivity of the sensor does not change monotonously.Through the integration of refractive index sensing sensitivity and full width at half maximum,figure of merit is presented and regarded as the optimized objective.The optimal design is achieved in the case of the fiber residual thickness for 66.5 μm,and the silver film thickness for 50 nm.The optimized design with the figure of merit of 98.67 is expected to be applied in the bio-chemical sensing and analysis.