Sensitivity of PANDA high-birefringence fiber loop mirror with temperature sensing

Abstract

With surrounding temperature changing, the shifting characteristics of the filtered spectrum of Panda high birefringence loop mirror are researched, according to the birefringence laws of Panda high-birefringence fiber and filter properties of the high-birefringence fiber loop mirror. Its sensitivity coefficient is up to 1.4219×10^-9m/°C. The transmission spectrum is shifted to short wave band, and the temperature sensitivity is 20 times higher than that of the fiber grating sensors, when the temperature rises up. This temperature sensing sensitivity is simulatated when the structural parameters are changed, such as the stress area's radius expressed as R, the high-birefringence optical fiber's length denoted as L and the distance between the core of the fiber and the stress area's central point marked as d. While the stress area's radius and the high-birefringence optical fiber's length are increased, the temperature sensitivity of the Panda high-birefringence loop mirror would become larger in its absolute value correspondingly. On the contrary, the temperature sensitivity would descend as the distance between the core of the fiber and the stress area's central point is increased. Furthermore, the influence on the temperature sensitivity, which is induced by changing the internal structural parameters of the high-birefringence optical fiber, is up to 10,000 times greater than the impacts resulted in by varying the fiber length L with the high-birefringence fiber loop mirror.