Fast polarization scramblers based on forward and backward nonlinear interactions in optical fibers

We analyze two all-optical fiber-based fast polarization scramblers. In the first, a signal beam nonlinearly interacts with a co-propagating incoherent pump, whose fast temporal fluctuations induce an effective depolarization of the signal. In the second, the signal interacts with its backward replica generated and amplified by a reflective loop. Beyond an amplification threshold, the signal output polarization exhibits chaotic dynamics.