Nonlinear polarizers based on four-wave mixing in high-birefringence optical fibers

Parametric amplification or four-wave mixing in high-birefringence optical fibers may be exploited to implement a novel type of nonlinear polarizer. Such a device leads to the simultaneous amplification, frequency conversion, and repolarization of both signal and idler waves along one of the principal birefringence axes of the fiber, independently of the pump, signal, and idler input state of polarization, power, and frequency detuning. We discuss the conditions for the observation of polarization attraction in fiber optics parametric amplifiers operating with a pump in either the normal or the anomalous dispersion regime.