Raman Nonlinear Polarization Pulling in the Pump Depleted Regime in Randomly Birefringent Fibers

The polarization evolution of the pump and signal in Raman copropagating amplifiers is numerically investigated, by considering the nonlinear polarization rotation and the pump depletion effects. The signal and pump quality at the fiber output is evaluated. The intrinsic limitations of the nonlinear polarization pulling effect are determined.