精确的折射率测量可以深入的了解介质微小的物理或者化学变化。提出一种基于Kretschmann棱镜结构的SPR折射率检测方法。首先利用Mathematica软件重点分析Kretschmann模型结构下待测样品折射率变化对表面等离子体共振吸收峰的影响,得到吸收峰随样品折射率的变化关系。在此基础上,构建Kretschmann模型并进行了酒精与水混合溶液的折射率测量。最后得出该方法能够有效检测到样品反射谱曲线,且与理论曲线趋势基本一致,在1.33-1.36折射率范围内检测的灵敏度可达86.88 deg/RIU。本研究方案对研制表面等离子体共振折射率传感器具有良好的价值。
Accurate measurement of refractive index is considered to be a deep understanding of the tiny physical or chemical changes in the media. Therefore, a detection solution of surface plasmon resonance refractive index based on Kretschmann structure is proposed. According to software simulation on Mathematica, firstly the influence of change of refractive index of sample on the surface plasmon resonance absorption peak is analyzed in Kretschmann model structure. And the trend of absorption peaks with the change of sample refractive index is obained. On this basis, experimental model of Kretschmann is constructed, and refractive index measurements of mixed solution of alcohol and water are carried out. The results indicate that the reflection spectrum curve of sample can be effectively detected, and basically consistent with the theoretical analyses, and the sensitivity of the sensor is up to 86. 88 deg/RIU in the range of 1. 33 to 1. 36. The study has some benefits for the development of the refractometer based on surface plasmon resonance technology.