Surface-mode induced high birefringence in a low-loss 7-cell photonic bandgap hollow-core fiber

Abstract

In this paper, a low-loss high-birefringence 7-cell photonic-bandgap hollow-core fiber (PBG-HCF) is designed and fabricated based on the method of surface mode engineering. Within a smooth transmission band from 1472 nm to 1560 nm, a minimum attenuation of 39 dB/km is measured where up to 3.29*10^-3 group birefringence is achieved. The windowed Fourier transform (WFT) is applied in the analysis of spectral beating measurement results. The wavelength dependence of group birefringence of fundamental and higher-order modes is resolved.