Performance Analysis of SPR Sensor Based on Polymer-tipped Optical Fiber Coated with Barium Titanate Layer

Abstract

In this paper, an optical fiber SPR sensor based on polymer-tipped optical fiber (PTOF) coated with a gold film and a Barium Titanate (BaTiO3) layer has been designed and analyzed by finite difference time-domain (FDTD) method. Three SPR dips are observed and the sensitivity is proved to be higher than the structure without BaTiO3. A novel measurement method based on sum-value and difference-value of two SPR dips is proposed. Compared with conventional measurement method based on single dip, the measurement based on sum-value can significantly improve the sensitivity and the measurement based on difference-value can effectively reduce the environmental influence.