Coupling Analysis Of The Polarization Maintaining Photonic Crystal Fiber With Superluminescent Diodes

Photonic crystal fiber (PCF) consisting of its high birefringence factor, temperature stability, flexible structural design and free from nuclear radiation, has replace the traditional polarization maintaining fiber used for the core component of the optical fiber sensors in the field of outer space and nuclear radiation. The paper based on National Natural Science Foundation project" FOG Development based on polarization maintaining the photonic crystal fiber ", research in the polarization characteristics of the photonic crystal fiber and the structure of PM-PCF which can be used to develop a high-polarization maintaining FOG The paper propose a new inner cladding structure with near elliptic refractive index distribution., and prove that this Near-Elliptic Inner Cladding PCF, not only has a good high birefringence properties in ideal circumstances, but its birefringence only has a very small deterioration when deviating from ideal structure. In ensuring high birefringence and polarization-stability, the paper further propose some structural changes to obtain a small-diameter field of high birefringence photonic crystal fiber, then further analyze this fiber used in FOG, and its coupling with SLD. This fiber has a broad prospect in the fiber optic gyroscope as the representative in the field of fiber sensor.The main researches in the thesis are as follows:1. Polarization Maintaining Photonic Crystal Fiber is analyzed in its structure, working mechanism, and other characteristics. PM-PCF has much higher birefringence than traditional PCF.2. The project team propose a new type of PM-PCFs used in high-polarization stable fiber optic gyroscope. The paper analyze the mode field distribution and birefringence properties of this new structure of PCF in three different structure perturbation, and verify that this fiber has a stronger ability to resist structural perturbation.3. The paper analyzes the mode field of SLD and PM-PCF, and their coupling characteristics. Further more, the analysis of the coupling efficiency and extinction ratio in different coupling angle and offset distance are proposed in this dissertation.