Propogation of broadband optical radiation in spun fiber with high birefringence

Polarization state evolution of the broadband optical radiation propagating in a spun fiber with high birefringence was studied. A theoretical model describing polarization state of radiation in the spun fiber at arbitrary polarization parameters of input radiation was developed. The model is based on a geometric analysis of polarization state distribution of radiation spectral components on the Poincare sphere. It is shown that above a certain length of propagation in the fiber (coherence length) averaged over the spectrum polarization state of the light radiation at the fiber output is determined by the parameters of spun fibers only, and the radiation polarization degree at the fiber output depends on the input polarization parameters.