The Impact of a High Differential Group Delay Section on the Output State of Polarization of Propagating Light

Research to date has shown that high differential group delay (HiDGD) sections along an optical fiber network link are the major contributors to PMD. PMD has deleterious effects on propagating optical signals. In this paper, we show the effect a HiDGD section has on the output state of polarization (SOP) of propagating light. Experimental results in this paper show a reduction in the range of the output SOP spread with an increase in the DGD of the HiDGD section to a given asymptote (a minimum) i.e. when HiDGD >= 35ps. However, the output SOP spread and its asymptote solely depends on the location of the HiDGD section along the fiber link length. A small output SOP spread over the entire wavelength scan covers a few polarization states on the Poincare sphere and vice versa for a large output SOP spread. The small output SOP spread over the entire wavelength range (50 nm in steps of 0.3 nm for this study) is an indicator that the polarization capabilities of optical telecommunication signals are restricted to minute SOPs.