Investigation Of Tellurite Photonic Crystal Fiber Polarization Beam Splitter

In the field of optical fiber communication,polarization beam splitter is an indispensable important optical element,with the development of optical communication technology,the traditional polarization beam splitter is difficult to integrate,the volume is too large,the shortcoming of low extinction ratio is increasingly revealed,the design of polarization beam splitter based on photonic crystal fiber,compared with the traditional polarization device just has the advantages of a small size,easy access to photonic circuits,and high-extinction ratio.Based on the flexible structure design and excellent optical properties of photonic crystal fiber,the polarization characteristics of single-core,dual-core and three-core tellurite photonic crystal fiber were studied.The structure design of tellurite photonic crystal fiber polarization beam splitter was realized.The main researches are as follows:Firstly,the numerical calculation methods for photonic crystal fiber are introduced,the finite element method and the fiber modeling simulation software which are used in this paper are analyzed emphatically.Secondly,a single-core tellurite photonic crystal fiber polarization beam splitter is designed.The propagation mode,effective refractive index,confinement loss and extinction ratio of the polarization beam splitter are studied in detail by finite element method.A single-core photonic optical fiber with good polarization characteristic was obtained,the fiber polarization beam splitter at two different wavelengths both have good polarization characteristics.Thirdly,a simple two-core photonic crystal fiber polarization beam splitter is studied.The vector finite element method is used to simulate the change of the mode field,normalized power and extinction ratio in the fiber under different structural parameters,and the performance of the polarization beam splitter has been improved by structural optimization.Finally,based on the principle of resonant coupling,a three-core tellurite photonic crystal fiber polarization beam splitter is proposed.By adjusting the structural parametersand simulation analysis have finally obtained a three-core optical fiber polarizing device with better performance than most polarization beam splitter,the polarization beam splitter has excellent characteristics such as short length,high extinction ratio,simple structure and easy preparation.