Distributed measurement of polarization crosstalk in polarization-maintaining anti-resonant hollow-core fibers

Polarization-maintaining anti-resonant hollow-core fibers combine the advantages of a hollow core with birefringence-protected light guiding, delivering promises for a wide range of applications. However, a comprehensive assessment of its polarization maintenance capability remains elusive. In this work, we demonstrate a distributed measurement of polarization crosstalk in this type of fiber utilizing modified optical frequency domain polarimetry. To address the substantial chromatic dispersion of group birefringence, a compensation approach is employed to rectify measurement inaccuracies stemming from the broadening of polarization crosstalk peaks. Using this method, we quantify the polarization crosstalk level in this type of fiber and explore distributed measurement of polarization crosstalk under three primary mechanical stresses: macro bending, transverse compression, and twisting.