Quasi-phase-matched 1.064-microm-pumped optical parametric oscillator in bulk periodically poled LiNbO(3).

We report a quasi-phase-matched optical parametric oscillator, using bulk periodically poled LiNbO(3). The optical parametric oscillator, pumped by a 1.064-microm Q-switched Nd:YAG laser, was temperature tuned over the wavelength range 1.66-2.95 microm. The oscillation threshold of approximately 0.1 mJ was more than a factor of 10 below the damage limit. The LiNbO(3) crystal, fabricated by application of an electric field to a sample with liquid and metal surface electrodes, was 0.5 mm thick with a 5.2-mm interaction length and a quasi-phase-matched period of 31 microm.