We report a widely tunable quasi-phase-matched optical parametric oscillator that uses periodically poled LiNbO3with a multigrating structure. The device is tuned by translation of the crystal through the resonator and pump beam, with no realignment needed. With a 1.064-µm acousto-optically Q-switched Nd:YAG pumplaser, we produced noncritically phase-matched tunable IR output from 1.36 to 4.83 µm. The threshold was 6 µJ for a 26-mm interaction length. The extraordinary polarization of LiNbO3 has better IR transmission than does the ordinary polarization, permitting operation at longer wavelengths with d33 quasi-phase matching than with conventional Type I birefringent phase matching.
© 1996 Optical Society of America
L. E. Myers, R. C. Eckardt, M. M. Fejer, R. L. Byer, and W. R. Bosenberg, "Multigrating quasi-phase-matched optical parametric oscillator in periodically poled LiNbO3," Opt. Lett. 21, 591-593 (1996)