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 μm). The fibers are fabricated by extrusion and subsequent drawing, using two different glasses: tellurite (70TeO
₂
-13ZnO-10BaO-7Na
₂
O), and chalcogenide (IG3, Ge
₃₀
As
₁₃
Se
₃₂
Te
₂₅
). The fabricated tellurite AR-HCFs can operate from 5 to 7 μm wavelength, and the IG3 AR-HCFs can operate further up to 11 μm 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 μm) should be possible, making this solution attractive for the mid-IR laser delivery, such CO, CO
₂
and quantum-cascade lasers.