Highly birefringent polarization maintaining low-loss single-mode hollow-core antiresonant fiber

In this paper, a highly birefringent polarization maintaining low losses and a single mode antiresonant hollow core fiber is proposed and analyzed, that is able to exhibit better performances compared to the recent related structures. The usage of bi-thickness cladding tubes with additional high refractive index layers on our geometrically optimized structure improves birefringence nearly by one order: the highest birefringence is 4.7 x 10-4 at 1.51 pm and sustains > 1 x 10-4 for a wide bandwidth of 100 nm with a larger core diameter of 26 pm. Elliptical nesting on our proposed structure lowers the confinement loss to 0.007 dB/m at 1.51 pm and maintains a loss of < 1 dB/m for a wide range of 210 nm. A polarization extinction ratio of 300 and higher order mode extinction ratio of 63, for our fiber, ensure a single polarization and single mode operation at 1.51 pm. Moreover, the proposed fiber exhibits a bend robust performance with a very low bend loss of 0.009 dB/m at a small bend radius of 6 cm and sustains a bend loss of < 0.01 dB/m from a bend radius of 4 cm and above. Hence, our presented fiber, containing the above excellent characteristics, may be fruitful for designing polarization-controlled devices (fiber optic sensors, fiber optic amplifiers, fiber optic gyroscope, etc.) in the field of optical communication.(c) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement