摘要
In this paper, we propose and experimentally demonstrate a compact optical fiber sensor based on a Mach-Zehnder in- terferometer (MZI) cascaded with fiber Bragg grating (FBG) for simultaneous measurement of refractive index (RI) and temperature. In order to get a proper spectrum, we discuss the effects of different structure parameters of MZI. Using the resonant wavelength of the FBG (DipFBG) and the interference dip of the MZI (Dipl), the RI and tempera- ture of the surrounding medium can be determined. The sensor has good operation linearity. The experimental results show that the distinctive spectral sensitivities are 0.071 75 nm/℃and -91.766 67 nm/RIU (refraction index unit) for Dip1 and 0.009 09 nm/℃ for DipFBG.
基金
supported by the National High Technology Research and Development Program of China(No.2013AA014200)
the National Natural Science Foundation of China(No.11444001)
the Municipal Natural Science Foundation of Tianjin(No.14JCYBJC16500)