Temperature and Refractive index sensor based on an etched thin core fiber

A novel fiber in-line Mach-Zehnder interferometer (MZI) is demonstrated for temperature and refractive index measurements. The sensor is formed by splicing a section of etched thin core fiber (TCF) between two single mode fibers (SMFs). Experimental results show that, high temperature sensitivity of 198.5pm/°C with a temperature variation of 40°C is achieved. The Refractive index (RI) response of the sensor is also investigated; the RI sensitivity is up to -66.305 nm/RIU within the RI range of 1.3286 - 1.3668.