Nonlinear repolarization dynamics in optical fibers: transient polarization attraction

In this work we present a theoretical and experimental study of the response of a lossless polarizer to a signal beam with a time-varying state of polarization. By lossless polarizer we mean a nonlinear conservative medium (e.g., an optical fiber) which is counter-pumped by an intense and fully polarized pump beam. Such medium transforms input uniform or random distributions of the state of polarization of an intense signal beam into output distributions which are tightly localized around a well defined state of polarization. We introduce and characterize an important parameter of a lossless polarizer – its response time. Whenever the fluctuations of the state of polarization of the input signal beam are slower than its response time, a lossless polarizer provides an efficient re-polarization of the beam at its output. Otherwise if input polarization fluctuations are faster than the response time, the polarizer is not able to re-polarize light.