Acta Photonica Sinica ›› 2010, Vol. 39 ›› Issue (7): 1216-1222.doi: 10.3788/gzxb20103907.1216

• Film Optics • Previous Articles     Next Articles

Traditional Approximate Theory and Thin Film Optical Theory in SPR

ZHANG Jiang-tao, GU Zheng-tian, DENG Chuan-lu   

  1. (Laboratory of Photo-electric Functional Films, College of science,University of Shanghai for Science and Technology, Shanghai 200093,China)
  • Received:2009-10-22 Revised:2009-12-31 Online:2010-07-25 Published:2010-07-25
  • About author:was born in 1983. He is pursuing the M. S. degree and his research interests focus on the theory and the application of SPR long-period fiber grating sensor coated with thin films.

Abstract:

In order to solve the problem that traditional SPR theory is approximate when determining parameters of metal film based on Kretschmann geometry, the strict thin film optical theory is introduced. SPR attenuation curve is obtained with characteristic matrix of film system. The results show that there exists differences in resonance angle and amplitude of reflectivity between approximate SPR theory and thin film optical theory. Contour map of resonance angle deviation shows variation of resonance angle deviation under different dielectric constants of metal film. Further experimental study shows that the simulation result of thin film optical theory is more consistent with experimental data than of approximate SPR theory. Finally the sensitivity of SPR sensor is discussed using approximate SPR theory and thin film optical theory respectively, and as a result, there is great difference in distribution region of sensitivity. Optical parameters of metal film can be determined more exactly using thin film optical theory, and accurate parameter combinations must be benefit to design high sensitivity SPR sensors.

Key words: Physical optics, Surface plasmon resonance, Thin film optical theory, Characteristic matrix, Resonance angle, Sensitivity

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