基于介电近零材料的空芯反谐振光纤双折射增强及单偏振单模特性研究

空芯反谐振光纤因可引导光在空气中传输而在高功率光传输和气体检测等传感领域有广泛应用前景，但其保偏性能仍有不足，会引起信号间串扰，严重影响系统稳定性。针对现有保偏空芯反谐振光纤宽带双折射较低、结构复杂、偏振损耗差较小等问题，本项目拟利用介电近零（ENZ）材料的局域电磁场增强效应，通过有效调节光纤模式的电磁场分布，提出一种基于ENZ的空芯反谐振光纤保偏性能增强的方法。主要研究内容：1基于本人在保偏光纤和ENZ领域的研究基础，选择合适的ENZ；2通过结合材料分布各向异性与结构各向异性，在保持光纤结构简单的前提下，拟将宽带双折射提高一个数量级；3将高双折射空芯反谐振光纤的设计思路用于单偏振单模光纤的设计，拟将偏振损耗差异在100nm带宽内提升至100dB/m以上。本项目的顺利实施有望探索出一种简单、高效的空芯反谐振光纤保偏性能增强方法，丰富了保偏空芯光纤的选择范围，提高其在光通信和传感的应用价值。

Hollow core anti-resonant fiber (HC-ARF) has a wide application prospect in the sensing fields of high-power optical signal transmission and gas detection due to its guiding capacity of the light transmission in the air. However, polarization maintaining performance is still insufficient, which leads to crosstalk between signals and seriously affects the stability of the system. Focus on the problems of low broadband birefringence, complex structure, and small polarization loss difference of the existing polarization maintaining HC-ARFs, this project plans to use the local electromagnetic field enhancement effect of epsilon- near-zero (ENZ) material to effectively adjust the field distribution of fiber modes, and propose a method to enhance the polarization maintaining performance of HC-ARF based on the introduction of ENZ in the fiber cladding. Main research contents: 1. Based on the applicant’s research experiences in the field of polarization maintaining fiber and ENZ property, select the appropriate ENZ material for the designing of the high-performance polarization maintaining HC-ARF; 2 by combining the material distribution and structural anisotropies, the broadband birefringence is to be increased by an order of magnitude on the premise of maintaining the simple structure of the HC-ARF; 3 the design idea of high birefringence hollow core anti resonant fiber is applied to the design of single-polarization single-mode HC-ARF, which would increase the polarization loss difference over 100dB/m within 100nm bandwidth. The successful implementation of this project is expected to develop a simple and efficient method to enhance the polarization maintaining performance of HC-ARF, enriching the polarization maintaining hollow core fiber and extending its application in optical communication and sensing.