Wideband and ultra-low confinement loss nested hollow-core anti-resonant fiber with double-single-layer structures

To further reduce the confinement loss of hollow-core anti-resonant fibers (HC-ARFs), broaden the low-loss operating bandwidth, and decrease the bending losses, this paper proposes a novel double-single-layer nested HC-ARF. The influence of structural parameters on its optical performance is analyzed using the full-vector finite element method, and the relevant structural parameters are optimized accordingly. The results indicate that, after optimizing the structural parameters, the HC-ARF exhibits extremely low confinement loss (on the order of 10^–8 dB/km) at the wavelength of 1.55 μm. When the bending radius is 10 cm, the bending loss is also very low (on the order of 10^–4 dB/km), which demonstrates an excellent bend-resistant property. Moreover, the HC-ARF possesses a very flat dispersion characteristic, with a low-loss operating bandwidth of approximately 945 nm, covering all the communication bands (O + E + S + C + L band).

Graphical Abstract

Cross section of the proposed double-single-layer nested HC-ARF and its Performance under the optimized structural parameters. This paper presents a new type of hollow - core anti - resonant fiber. The optical properties of this fiber, including confinement loss, bending loss and dispersion, etc., are numerically calculated by using the full-vector finite-element method. On this basis, the structural parameters of the fiber are optimized, and excellent optical properties are finally obtained.