双金属层表面等离子体共振传感器灵敏度优化

为了优化表面等离子体共振传感器的灵敏度，基于薄膜光学理论，分析了银-金双金属层表面等离子体共振传感器的反射率和灵敏度随金属薄膜厚度变化的规律。发现在满足共振角反射率小于1%的条件下，银膜和金膜厚度存在一定的取值范围; 在此厚度范围内，传感器的灵敏度随着金属薄膜（银膜与金膜）厚度的增大而提高，灵敏度增量最大可达5°/RIU。结果表明，在保证一定共振角反射率的前提下，可通过增加双金属层中金属薄膜的厚度提高双金属层表面等离子体共振传感器的灵敏度。

Sensitivity optimization of bimetallic film surface plasmon resonance sensor

To optimize the sensitivity of surface plasmon resonance(SPR)sensors,the reflectivity and sensitivity variances of bimetallic film SPR sensors with the change of silver-gold film thickness were studied based on thin film theory.The thickness of silver film and gold film had a certain range under the condition that resonance angle reflectivity was less than 1％.In the range of thickness,the sensitivity of bimetallic film SPR sensor increases with the increase of the thickness of silver film(or gold film).The increment of sensitivity was up to 5°/RIU.The results indicate that the sensitivity of bimetallic film SPR sensor can be improved by increasing the thickness of bimetallic film under the premise of certain resonance angle reflectivity.