Extruded Antiresonant Hollow Core Fibers for Mid-IR Laser Delivery

We report an overview of our recent progress in the design and fabrication of soft-glass based antiresonant hollow core fibers (AR-HCFs) for laser delivery in the mid-IR (5 - 11 mu m). The fibers are fabricated by extrusion and subsequent drawing, using two different glasses: tellurite (70TeO(2)-13ZnO-10BaO-7Na(2)O), and chalcogenide (IG3, Ge30As13Se32Te25). The fabricated tellurite AR-HCFs can operate from 5 to 7 mu m wavelength, and the IG3 AR-HCFs can operate further up to 11 mu m wavelength. The numerical and experimental losses of the fundamental mode for the fabricated fibers are on the few dB/m level. Numerical modeling study indicates that, by improving the uniformity and shape of the capillaries, losses down to 0.1 dB/m in the mid-IR (5 to 11 mu m) should be possible, making this solution attractive for the mid-IR laser delivery, such CO, CO2 and quantum-cascade lasers.