Self-organization of the state of polarization in the mid-point of telecommunication optical fibers

We investigate theoretically and experimentally a self-polarization attraction process occurring in telecommunication optical fibers for which two replicas of an arbitrary polarized incident signal (up to a rotation or a reflection through a plane of the state of polarization) are injected simultaneously at both ends of an optical fiber. This polarization effect is based on a counter-propagating four-wave mixing process also called nonlinear cross-polarization interaction. In this configuration, the spatio-temporal dynamics relaxes towards a stationary trajectory, which is characterized by a well-defined state of polarization (point or line) in the middle point of the fiber. We show that the structure and the position of this state can be controlled through the boundary conditions at both ends of the fiber. Moreover, we discuss the efficiency of the attraction process as a function of the fiber length and the power ratio of the two beams. (C) 2019 Optical Society of America