Study On SPR-Based Gold Coated Microstructure Fiber Polarization Device

With the continuous development of optical communication technology,people are increasingly relying on large-capacity and efficient information transmission,so the demand for matching polarizing optical devices is becoming stronger and stronger.The existing optical devices should also tend to be small and the emergence of integration and microstructured optical fibers has strongly promoted this evolution.In recent years,people have even introduced metallic surface plasmon resonance effects by adding metallic materials inside,thereby further improving the performance of microstructured polarizing devices.Starting from the microstructure fiber polarization device based on the plasmon resonance effect on the metal surface,the characteristics of loss,bending,bandwidth,mode field area,and dispersion of related fiber polarization devices are studied.The main chapter arrangements and research contents of this article are as follows:Firstly,the research background and significance of this topic are briefly introduced,and the current research status of micro-structured fiber polarization devices based on the plasmon resonance effect of metal surfaces is carefully analyzed.At the same time,the related theoretical knowledge of the plasmon resonance effect on the metal surface and the full vector finite element method are described.Secondly,a gold-coated microstructured optical fiber filter based on surface plasmon resonance was designed.According to the plasmon resonance effect of the metal surface and the light guiding mechanism of the microstructure fiber,combined with the influence of geometric parameters on the filtering performance,one mode of the core is coupled with the mode supported by the gold layer surface,and finally the filtering characteristics are realized.Thirdly,a gold-coated liquid crystal core microstructured optical fiber filter based on surface plasmon resonance was designed.The effects of air hole spacing,air hole size,and rotation angle of liquid crystal molecules on the performance of microstructured optical fiber filters were studied.The correlation performance of the structured fiber filter is compared and analyzed.Finally,a gold-coated single-mode single-polarization microstructured optical fiber based on surface plasmon resonance is designed.Combined with the mode coupling theory,the mode energy to be filtered is lost through coupling and absorption.Meanwhile,the effects of geometric parameters on single-mode single-polarization characteristics were studied,and the performance characteristics of single-mode single-polarization microstructure optical fibers based on the plasmon resonance effect of metal surfaces under different structures were analyzed.