Low-Loss Fusion Splice of Hollow-Core Anti-Resonant Fiber and Single Mode Fiber

Photonic crystal fibers have attracted intensive attention because of its advantages of a freedom design and a novel light guiding mechanism. Compared with photonic bandgap fibers and Kagome fibers, the hollow-core anti-resonant fibers (HC-ARF) exhibit excellent optical properties in terms of simple structure, single mode transmission, broad transmission bandwidth and low optical attenuation. HC-ARF is suitable for UV/mid-1R light transmission, high power laser generation, nonlinear optics, sensing and so on. However, in order for HC-ARF to be widely used, the fusion of HC-ARF and a conventional single-mode fiber must be simple and low-loss. While, because the special cladding capillaries of HC-ARF arc easily destroyed during splicing, and the mode field of HC-ARF is different with single mode fiber, the direct splicing technique easily leads to a large loss. So we use a solid core large mode area fiber with a core diameter of 20 mu m as an intermediate, to obtain a low-loss fusion splice between a HC-ARF and a conventional single mode fiber. Compared to the direct splicing technique, which yields a splice loss of 3 dB, the intermediate fiber technique makes the overall insertion loss decrease to 0.844 dB.