Performance characterization and guidelines for the design of a counter-propagating nonlinear lossless polarizer

We characterize the performance of a nonlinear lossless polarizer, an all-optical fiber-based device that allows for the control of the state of polarization of an optical signal. The device relies on the lossless polarization attraction generated by the nonlinear interaction between the controlled signal and a controlling pump. Choosing a counterpropagating pump, we quantify its performance by introducing the degree of attraction (DOA), which highlights the trade-off between the average attraction of the signal polarization and the unavoidable degradation of its degree of polarization (DOP). We investigate, by numerical simulations, the dependence of the DOA on the injected power and on the fiber length, thus providing the design guidelines to reach the desired performance. We find that an effective attraction can occur even for strongly unbalanced signal and pump power levels, and that fibers longer than a few kilometers yield only a marginal improvement of the DOA.