We report a ring-assisted few-mode fiber design with large mode effective index difference (△) and low loss. By introducing the low-index ring-assisted structure in the cladding, the effective indexes of LP₁₁, LP₂₁ and LP₀₂ modes can be greatly reduced, while the effective index of LP₀₁ mode is almost unaffected. Also, we find that introducing multiple ring-assisted structures will help reduce loss. The proposed few-mode fiber has potential application value for improved mode-division multiplexing optical fiber communication system.

中文翻译：

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用于改进模分复用的低损耗环辅助少模光纤的设计

我们报告了一种具有大模式有效折射率差 (△ ) 和低损耗的环辅助少模光纤设计。通过在包层中引入低折射率环辅助结构，LP ₁₁、LP ₂₁和LP ₀₂模式的有效折射率可以大大降低，而LP ₀₁模式的有效折射率几乎不受影响。此外，我们发现引入多个环辅助结构将有助于减少损失。所提出的少模光纤对于改进的模分复用光纤通信系统具有潜在的应用价值。