A Study on Novel Applications of Solid-Core Photonic Bandgap Fibers

在本研究中，我们研究了固体核光子带隙光纤（SC-PBGFs）的传输特性，旨在实现高功率掺镱光纤激光器和放大器的大模面积（LMA）和有效的单模工作，并具有实际允许的弯曲半径。通过基于有限元法的详细数值模拟，我们评估了光子带隙阶数对弯曲性能的影响，并指出了单芯结构的SC-PBGFs由于弯曲损耗的增加而导致芯尺寸增大的极限。此外，在实际约束下，我们发现具有7芯芯的SC-PBGFs可以在基模和高阶模之间获得足够的差分弯曲损耗，并且与之前报道的指数导向LMA光纤相比，有效面积限制要大得多。

In this study, we investigated the propagation characteristics of solid-core photonic bandgap fibers(SC-PBGFs) aiming to achieve large mode area(LMA) and effectively single-mode operation with a practically allowable bending radius for high-power Yb-doped fiber lasers and amplifiers. Through detailed numerical simulations based on the finite element method(FEM), we evaluated the impacts of the order of photonic bandgap on the bending performance and pointed out the limits of core-size enlargement in the SC-PBGFs with a one-cell core structure due to the increment of bending loss. In addition, under practical constraints, we found that the SC-PBGFs having a seven-cell core can achieve sufficient differential bending loss between the fundamental mode and the higher-order modes and a much larger effective area limit as compared with previously-reported index-guiding LMA fibers.