Low-penalty Phase De-multiplexing of QPSK Signal by Dual-pump Phase Sensitive Amplifiers

We demonstrate phase de-multiplexing of QPSK signal to BPSK signals based on dual-pump phase sensitive amplifiers by controlling and stabilizing the gain axis. The de-multiplexed BPSK signals have an OSNR penalty less than 1-dB compared to the back-to-back BPSK signals.