Temperature Characteristic of SMPMS Fiber Structure-Based Sagnac Loop

A novel, cost-efficient all-fiber temperature sensor is proposed and demonstrated experimentally. The sensor consists of single-mode-multimode-polarization-maintaining-multimode-single-mode fiber structure reeled into a circle based on a Sagnac loop. Its temperature characteristic is investigated experimentally. The temperature sensitivity reaches up to 1.476 nm/°C for the radius of 7 cm. Experimental results show that the radius has significant influence on temperature sensitivity and the theoretical analysis is expressed.