中心辅助环芯光纤的模式调控特性及其控制规则

doi:10.3969/j.issn.0255-8297.2025.06.001

摘要/Abstract

摘要： 近年来空分复用技术广泛用于提升光纤通信容量，空分复用光纤是达成这一目标的关键基础。其中弱耦合少模光纤通过降低模式间耦合，能够有效抑制模间串扰，显著降低传输系统的复杂度与成本。本文回顾了不同结构类型的弱耦合少模光纤,详细介绍了本课题组针对中心辅助环芯光纤的研究，实现了在常规通信光纤芯包折射率差水平下，模式空间简并显著分离、偏振简并基本不分离的设计目标，且具备良好的工艺误差容限；发现了用于调控空间简并模式分离的中心辅助环芯光纤设计规则，揭示了该类光纤通过改变光纤折射率剖面对称性调控特定空间模式简并分离的规律，为同类光纤结构设计提供有益指导。

关键词: 空分复用, 弱耦合少模光纤, 中心辅助环芯光纤, 简并模式

Abstract: In recent years, space division multiplexing (SDM) technology has been extensively utilized to enhance the capacity of optical fiber communications, with SDM fibers serving as the key enabling foundation. Among them, weakly coupled few-mode optical fibers reduce inter-mode coupling, effectively suppress mode crosstalk, and significantly lower the complexity and cost of the transmission system. In this paper, different structural types of weakly coupled few-mode fibers, and the work undertaken by our research team on center-assisted ring-core fibers are presented. Center-assisted ring-core fibers achieve the design objective of significantly separating spatial mode degeneracy while keeping polarization degeneracy unseparated under the conventional core-cladding refractive index difference level of communication fibers, and exhibit good tolerance to fabrication errors. Furthermore, design rules for controlling the separation of spatial mode degeneracy in center-assisted ring-core fibers are identified, unveiling the principle of regulating specific spatial mode separations by altering the symmetry of the fiber’s refractive index profile. The results provide valuable guidance for the design of similar fiber structures.

Key words: space division multiplexing (SDM), weakly coupled few-mode fiber, center-assisted ring-core fiber, degenerate mode

中图分类号:

O436

郑晶晶, 叶萧, 宋豫婧, 裴丽, 宁提纲. 中心辅助环芯光纤的模式调控特性及其控制规则[J]. 应用科学学报, 2025, 43(6): 893-908.

ZHENG Jingjing, YE Xiao, SONG Yujing, PEI Li, NING Tigang. Mode Regulation Characteristics and Control Rules of Center-Assisted Ring-Core Fiber[J]. Journal of Applied Sciences, 2025, 43(6): 893-908.

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