差分表面等离激元共振传感仿真研究

从薄膜光学理论出发,对不同金属膜厚度、不同实折射率和不同复介电常数的环境介质的表面等离激元共振(SPR,Surface Plasmon Resonance)信号进行了分析,给出了最佳金属膜厚度,并且,折射率与共振角呈线性关系(R=0.999 4).分析了采用差分处理时,随环境介质的复介电常数变化的光反射率曲线.结果表明,同组两个探测器信号的和随环境介电常数的虚部变化,与实部无关,其信号差则相反,因此,能够同时测量环境介质的介电常数的实部和虚部.

Simulation of Differential Surface Plasmon Resonance Sensing

The effects of different film thickness,different real refractive index and different complex dielectric constant on the signal of surface plasmon resonance was analyzed based on film optics theory.The optimal film thickness was given,and the relationship between refractive index and resonance angle is linearity(R=0.999 4).The refractivity of complex dielectric constant with differential processing was also researched,which demonstrated that the addition of signals of two detectors in the same set changes with the virtual part of complex dielectric constant,however,is independent from the real part of complex dielectric constant,which is opposite to the difference of two signals.So,the real and virtual parts of complex dielectric constant can be monitored at the same time.