Multi-channel phase regenerator based on polarization-assisted phase-sensitive amplification

We propose and demonstrate simultaneous phase regeneration of six nonreturn-to-zero binary phase shift keying signals in a single nonlinear medium. The regenerating system,which exhibits binary steplike phase transfer functions, uses four-wave mixing in degenerate dual-pump vector parametric amplifiers implemented in the same nonlinear optical fiber, followed by polarization filtering. Bit-error-ratio measurements confirm optical-signal-to-ratio improvement and negligible crosstalk across all the regenerated channels, which were impaired at the regenerator input by broadband phase noise.