Optical phase-sensitive amplificationusing two phase-locked light sources

Optical phase-sensitive amplification using individual pump and signal light sources is presented for the first time. In the experiment, optical phase of pump and signal light is locked by an optical phase-locked loop (OPLL). Stable optical phase-locking is achieved and optical phase-sensitive amplification with a gain of 12 dB is successfully demonstrated using a nonlinear Sagnac interferometer.