Nested capillary anti-resonant silica fiber with mid-infrared transmission and low bending sensitivity at 4000 nm

Mariusz Klimczak (1) , Dominik Dobrakowski (1) , Amar Nath Ghosh (2) , Grzegoçrz Stepniewski (1) , Dariusz Pysz (1) , Guillaume Huss (1) , Thibaut Sylvestre (2) , Ryszard Buczyński (1)

1 Institute of Electronic Materials Technology - Institute of Electronic Materials Technology
2 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)

We report a silica glass nested capillary anti-resonant nodeless fiber with transmission and low bending sensitivity in the mid-infrared around 4000 nm. The fiber is characterized in terms of transmission over 1700–4200 nm wavelengths, revealing a mid-infrared 3500–4200 nm transmission window, clearly observable for a 12 m long fiber. Bending loss around 4000 nm is 0.5 dB/m measured over three full turns with 40 mm radius, going up to 5 dB/m for full turns with 15 mm radius. Our results provide experimental evidence of hollow-core silica fibers in which nested, anti-resonant capillaries provide high bend resistance in the mid-infrared. This is obtained for a fiber with a large core diameter of over 60 μm relative to around 30 μm capillaries in the cladding, which motivates its application in gas fiber lasers or fiber-based mid-infrared spectroscopy of COx or NxO analytes.

Domaines: Optique [physics.optics]

Mariusz Klimczak, Dominik Dobrakowski, Amar Nath Ghosh, Grzegoçrz Stepniewski, Dariusz Pysz, et al.. Nested capillary anti-resonant silica fiber with mid-infrared transmission and low bending sensitivity at 4000 nm. Optics Letters, 2019, 44 (17), pp.4395 - 4398. ⟨hal-02371051⟩