Investigation of an All-Optical Black-Box PPLN-PPLN BPSK Phase Regenerator

We investigate the phase squeezing performance of an all-optical black-box binary phase-shift keyed phase regenerator constructed from periodically-poled lithium-niobate (PPLN) waveguides. Phase regeneration is performed with different levels of phase noise and constant amplitude noise added to the phase modulated input. We experimentally show that, for moderate phase noise, unwanted phase-to-amplitude noise conversion can be minimized without degradation of the phase squeezing performance, by controlling the signal-to-pump power ratio at the input to the PPLN-based phase-sensitive regenerator.