Low-Loss Chalcogenide Fiber Prepared by Double Peeled-Off Extrusion

We have developed an innovative extrusion with double peeling-off process to fabricate chalcogenide (GhG) preform, with an aim to remove the defects, such as bubbles, oxidation, and particles that always induce large optical losses in ChG glass fibers. As a result, none of the defects is found in the core-cladding interface of the fiber. The loss in a wavelength range of 5.5-8.2 μm is generally lower than 1 dB/m, with a minimum value of 0.2 dB/m at 6.3 μm. Moreover, a flat mid-infrared (MIR) supercontinuum (SC) spectrum spanning from 1.4 μm to 13.7 μm is generated in an 18 cm-long Ge-As-Se ChG fiber, accompanied with a highest spectrum flatten ratio of 72.4%.