Le. Myers et al., MULTIGRATING QUASI-PHASE-MATCHED OPTICAL PARAMETRIC OSCILLATOR IN PERIODICALLY POLED LINBO3, Optics letters, 21(8), 1996, pp. 591-593
We report a widely tunable quasi-phase-matched optical parametric osci
llator that uses periodically poled LiNbO3 with a multigrating structu
re. The device is tuned by translation of the crystal through the reso
nator and pump beam, with no realignment needed. With a 1.064-mu m aco
usto-optically Q-switched Nd:YAG pump laser, we produced noncritically
phase-matched tunable IR output from 1.36 to 4.83 mu m. The threshold
was 6 mu J for a 26-mm interaction length. The extraordinary polariza
tion of LiNbO3 has better IR transmission than does the ordinary polar
ization, permitting operation at longer wavelengths with d(33) quasi-p
hase matching than with conventional Type I birefringent phase matchin
g. (C) 1996 Optical Society of America.