Analysis of the polarization dependence of non-linear effects using high-resolution spectrally-resolved polarimetry

In this work a full characterization in the Stokes space is presented of diverse polarization issues associated with non-linear effects such as Cross Phase Modulation (XPM) and Four Wave Mixing (FWM). A high resolution spectral polarimetry technique has been applied that allows simultaneous visualization of the polarization parameters in the full spectral range of interest. The state of polarization of all the spectral components is obtained without filtering or isolating each component individually. The measurement technique that has been used is based on the polarization properties of Stimulated Brillouin Scattering (SBS), and is achieved by analyzing the polarization dependence of the spectral contribution of the SBS generated in the interaction of a given signal with a tunable optical pump. This allows a high resolution characterization of the polarization properties of the generated spectral components generated by non-linear effects. Without prior knowledge or alignment, all the polarization related impairments can be monitored. The source of the polarization related impairment can be arranged as a linear effect (Polarization Mode Dispersion) or non-linear effect (XPM). The complete information of the polarization states allows also full quantification of the non-linear interaction in the XPM and thus obtaining a value of the non-linear coefficient, n₂.