Temperature dependence of a refractive index sensor based on a bent core-offset in-line fiber Mach-Zehnder interferometer

摘要

A bent core-offset in-line fiber Mach-Zehnder Interferometer (MZI) as a refractive index (RI) sensor was fabricated by using a commercial fusion splicer. The temperature dependence on the so-obtained sensor was investigated. It showed that not only the RI sensitivity, but also the temperature sensitivity could be enhanced by reducing the bending radius. The variation of RI and the temperature hardly affected the sensitivity of each other within the margin of error. The wavelength-related measurement was used to realize the simultaneous measurement of RI and temperature. The highest temperature sensitivity of 0.11745 nm/degrees C and the highest RI sensitivity of -115.5646 nm/RIU was obtained by the sensor with a length of 30 mm, a core-offset of 6 mu m, and a bending radius of 25.42 mm.