摘要： Since the pioneering studies on polarization dynamics of two counter-propagating beams in nonlinear optical fibers, different processes of polarization attraction have been identified in isotropic fiber, but also in highly, weakly and randomly birefringent fibers. In this framework, the polarization attraction requires a fully polarized pump wave, which plays the role of a natural attractor for an arbitrary polarized incoming beam. Subsequently, this phenomenon has been observed using a single wave interacting with its own back-reflected wave in a feedback loop configuration. Here, we report a new configuration of polarization self-organization with two uncorrelated arbitrary polarized waves that occurs in the middle point of an optical isotropic fiber. The state of polarization (SOP) of the two counterpropagating waves evolves and fluctuates over the surface of the Poincaré sphere with a coherence time τc. During the propagation, the SOP is deeply modified by the nonlinear interaction: While the injected SOPs fluctuate all over the Poincaré spheres, the SOPs in the middle point of the fiber are attracted toward the poles of the spheres, which correspond to the circular polarization states of the fields. Then both waves recover a random state at their corresponding fiber outputs. This effect has been demonstrated experimentally considering 256 randomly distributed initial pulses in an 200-m long isotropic fiber.