A focal-ratio-degradation resistant multimode fiber-link using modes-selective photonic lantern
A focal-ratio-degradation resistant multimode fiber-link using modes-selective photonic lantern
复制标题
使用模式选择光子灯笼的抗焦比退化多模光纤链路
DOI：
10.1117/12.2561438
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Benoit A
中科院分区：
文献类型：
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作者：
Benoit A
我们报告了一种减轻多模光纤链路中焦比退化（FRD）的新途径。我们的方法使用具有不同纤芯的定制多芯光纤 (MCF)，然后在两端逐渐变细以形成多模纤芯并创建模式选择性光子灯笼 (PL) 转换。 MCF 的纤芯在 1550 nm 处为单模，并且间隔足够大，因此在 7 m 光纤长度后不会出现可观察到的纤芯间串扰。 MCF 两端的模式选择性 PL 与 1550 nm 处 MCF 的低纤芯间串扰相结合，可确保在整个光纤链路中保留每种空间模式的相对功率量。因此，使用这种方法的 PL-MCF-PL 链路有可能通过抑制光从低阶模式到高阶模式的耦合来抵抗 FRD。我们表明，与引导相同模式数量的定制多模光纤相比，完整的 PL-MCF-PL 链路表现出更低的 FRD。对 PL-MCF-PL 链路的 FRD 行为如何随波长变化的研究表明，由于 PL 的波长相关特性和 MCF 中的交叉耦合，存在一些带宽限制。
We report a new route to mitigate focal-ratio degradation (FRD) in multimode optical fiber links. Our approach uses a custom multicore fiber (MCF) with dissimilar cores, which is then tapered at both ends to form multimode cores and create mode-selective photonic lantern (PL) transitions. The cores of the MCF are single-moded at 1550 nm and sufficiently spaced such that there is no observable core-to-core cross talk after a 7 m fiber length. The mode-selective PLs at each end of the MCF, in combinations with the low core-to-core cross talk of the MCF at 1550 nm, ensure that the relative amount of power in each spatial mode is preserved throughout the fibre link. As such, a PL-MCF-PL link using this approach has the potential to be resistant to FRD by inhibiting the coupling of light from lower-order to higher-order modes. We show that the full PL-MCF-PL link exhibits lower FRD than a custom multimode fiber that guides the same number of modes. A study of how the FRD behavior of the PL-MCF-PL link varies as a function of wavelength indicates some bandwidth limitations due to the wavelength-dependent properties of the PLs and the cross coupling in the MCF.