Axial strain and temperature sensor based on tapered seven-core fiber operating at dispersion turning point

An axial strain and temperature sensor based on a tapered seven-core fiber (SCF) operating at the dispersion turning point (DTP) is proposed. The tapered SCF sensor with DTP was fabricated by the one-step tapering method, and its axial strain characteristics and temperature characteristics were simulated and experimentally investigated. The experimental results show that the tapered SCF sensor operates near DTP with the highest axial strain sensitivity and temperature sensitivity, consistent with the simulation results. The maximum axial strain sensitivity of the tapered SCF sensor is 391.2 pm/mu epsilon in the range of 0-300 mu epsilon, and the maximum temperature sensitivity is 6.44 nm/degrees C in the range of 30-70 degrees C. The sensor is highly sensitive to axial strain and temperature. It is promising for measuring physical quantities such as weak strain and temperature.