Wideband Low Loss Hollow Core Fiber With Nested Hybrid Cladding Elements

In this article, an antiresonant nodeless hollow core fiber having nested hybrid cladding elements is proposed without having large distance between core and jacket capillary. The presented anisotropic construction (elliptical nesting in circular tube) with optimized curvature factor, strut thickness, and gap between adjacent tubes lead to extremely low loss over wide band compared to existing structures (circular, circular nested, elliptical, elliptical nested). The results show the lowest confinement loss of 0.0007 dB/km at 1.06 $\mu$ m with maintaining a loss of less than 0.003 dB/km over 670 nm (0.90 $\mu$ m to 1.57 $\mu$ m) bandwidth. In addition, the lowest surface scattering loss of 0.01 dB/km is achieved along with better bending stability and effective single mode operation. The proposed fiber may have potential opportunity in optical communication systems for its low-loss transmission over wideband region.