Phase-transparent flexible waveband conversion of 43 Gb/s RZ-DQPSK signals using multiple-QPM-LN waveguides

We report phase-transparent waveband conversion with polarization insensitivity based on second harmonic (SH) wave pumped difference frequency generation (DFG) using multiple-quasi-phase-matched LiNbO(3) (QPM-LN) waveguides. Flexible waveband conversion is demonstrated over the entire C-band using a tunable DFB-LD array (TLA) as a pump source for a multiple-QPM-LN waveguide. The penalty free waveband conversion of 43 Gb/s return-to-zero differential quadrature phase-shift-keying (RZ-DQPSK) waveband signals is successfully achieved.