Refractive Index Sensor Based on S-Tapered Photonic Crystal Fiber

The S-tapered PCF interferometer for refractive index sensing was demonstrated in this letter. The whole fabrication process was carried out using a standard splicing machine. It has a compact and stable structure since the S-shape assumes the same function with elongating taper. The sensor exhibits highly SRI sensitivity, which is found to be 8.0 10
^-5
RIU in 1.38-1.44 and the temperature dependence is only 4.2 pm/°C low 100°C.