Phase sensitive degenerate parametric amplification using directly-bonded PPLN ridge waveguides.

We constructed the first CW pumped degenerate parametric amplifier based on periodically poled and ZnO-doped LiNbO3 ridge waveguides. An in-phase gain of + 11 dB was achieved owing to the high conversion efficiency and high damage resistance of the waveguide obtained by employing direct bonding and dry etching techniques. Nearly identical amplification and deamplification were obtained owing to a sufficient spatial and temporal overlap between the pump and signal beams. No secondary wavelength conversion process was observed, and a maximum output of 22 dBm was obtained. We also successfully demonstrated the phase sensitive amplification of a modulated signal light.