SOA-Assisted Data-Polarization-Insensitive Wavelength Conversion in a PPLN Waveguide

We demonstrate a novel method of wavelength conversion in a periodically poled lithium niobate (PPLN) waveguide using polarization modulation and amplitude modulation of its pump. Polarization-insensitive, all-optical, intensity-to-polarization conversion in a semiconductor optical amplifier (SOA) is used to reduce the waveguide's polarization sensitivity from >30 dB to <1 dB. We demonstrate BER measurements of the converted signal at 2.5 Gb/s. We also demonstrate polarization modulation of the PPLN waveguide pump using cross-polarization modulation in highly nonlinear fiber (HNLF) at 10 Gb/s.