组合锥型光纤SERS探针的理论设计与优化

Theoretical design and optimization of combination tapered optical fiber SERS probes

对组合锥型光纤表面增强拉曼(SERS)探针的结构参数进行了设计与优化。通过建立描述消逝波激发组合锥光纤探针表面纳米颗粒的激发光衰减系数模型,结合激发光经渐变锥段的全反射传输、探针平直段与激发光纤间的模式匹配原理,给出了组合锥型光纤SERS探针的结构参数设计与优化方法。利用该设计与优化方法,在给定光纤和纳米颗粒结构以及周围环境和激发光功率下,进行了光纤SERS探针结构参数的模拟设计。

The structural parameters of combination tapered optical fiber surface enhanced Raman scattering （SERS） probes were designed and optimized. By building the excitation light attenuation coefficient model based on evanescent wave excitation on the nanoparticle＇s surface of combination tapered optical fiber, and considering the total refraction theory of the excited light in the gradient core section and the mode- matching principle between the probe straight core section and the excitation fiber, the structure parameters design and optimization method of the combination tapered SERS probe were presented. With given fiber, nanoparticle structure, surrounding environment and input excitation power, an example of simulation design for the structural parameters of such optical fiber SERS probes were carried out by using the presented method.