Li Jie, Fan Pengcheng, Sun Li-Peng, Wu Chuang, Guan Bai-Ou
Opt Lett. 2018 Feb 15;43(4):655-658. doi: 10.1364/OL.43.000655.
We present a type of few-period helically twisted all-solid photonic bandgap fiber (AS-PBGFs). The helical structure leads to orbital resonance of a cladding rod light, which couples with the core mode. A two-period twist structure exhibits an extremely strong resonant dip of up to 30 dB. A series of samples with twist periods of 3.31-7.92 mm (yielding twist rates of 1.90-0.79 rad⋅mm) in association with different resonance orders are fabricated and demonstrated. The inherent physical mechanism underlying the resonance is analyzed. Moreover, the responses of the resonance to mechanical torsion, strain, and temperature are investigated. The twisted AS-PBGFs feature high reproducibility, stability, and robustness, and have great potential in tunable in-fiber filters and sensors.
我们展示了一种少周期螺旋扭曲全固态光子带隙光纤（AS-PBGFs）。这种螺旋结构导致包层棒状光的轨道共振，该共振与纤芯模式耦合。两周期扭曲结构呈现出高达30 dB的极强共振凹陷。制作并展示了一系列扭曲周期为3.31 - 7.92 mm（扭曲率为1.90 - 0.79 rad⋅mm）且具有不同共振阶数的样品。分析了共振背后的内在物理机制。此外，还研究了共振对机械扭转、应变和温度的响应。扭曲的AS-PBGFs具有高再现性、稳定性和鲁棒性，在可调谐光纤滤波器和传感器方面具有巨大潜力。
