The effect of temperature and electric current on the SPR sensors .

摘要

In this thesis, the history of SPR (Surface Plasmon Resonance) sensors and the details of the SPR theory and development are elucidated. An economical and practical SPR sensing reflectometer is introduced, including the manufacturing of the sensor film and measurement of the refractive indices of air and water.;Systematical theoretical simulations of multiple layer system SPR curves are developed. For this research, a NanoSPR 6 reflectometer with a ∼0.5% resolution and ∼2 sec response time is used. The dip of the SPR curve occurs at about 44.300 degrees, when the refractive indices of air and water are measured.;An integrated simulation of the temperature effects on a Kretschmann coupling configuration is modeled using Mathematica. The temperature effects of both the layers and the prism system are considered in this modeling. When the temperature is increased by 100 degree, the model shows that the minimum value of the SPR curve will shift to the right hand side by ∼0.08 degree; the intensity of the SPR will decrease by ∼ 3% and the full width at half maximum of the SPR curve will increase around 1.5 degree. We also shows that the electric current added to the gold film changed the SPR curve and find that the electromagnetic effect on the SPR curves is 10 times stronger than the temperature effect. An empirical formula is developed for the difference of the SPR curves (with current and without current) based on the experimental data using the Origin software. The reduced Chi-Square of the formula is 1.022x10 -6 and the probability distribution is 0.9826, which shows that the empirical formula fitted the data well.