The results of a simple scheme to generate continuously tunable pulsed narrow-bandwidth (less than 0.1 cm <sup>-1</sup>) light in the infrared are presented. A periodically poled lithium niobate (PPLN) optical parametric amplifier is seeded with the filtered output of a PPLN optical parametric generator. A high-finesse Fabry–Perot etalon is used as the filtering element, giving bandwidths as narrow as 0.08 cm <sup>-1</sup> and tunable over 18 cm <sup>-1</sup> without any adjustments to the PPLN crystals. High efficiency is obtained with a 15-ns 1-kHz Nd:YAG laser, giving energies of up to 180 µJ of signal at 1.6 µm and 60 µJ of idler at 3.3 µm .
© 1998 Optical Society of America
(190.1900) Nonlinear optics : Diagnostic applications of nonlinear optics
(190.4410) Nonlinear optics : Nonlinear optics, parametric processes
(190.4970) Nonlinear optics : Parametric oscillators and amplifiers
(300.6340) Spectroscopy : Spectroscopy, infrared
(300.6360) Spectroscopy : Spectroscopy, laser
P. E. Powers, K. W. Aniolek, T. J. Kulp, B. A. Richman, and S. E. Bisson, "Periodically poled lithium niobate optical parametric amplifier seeded with the narrow-band filtered output of an optical parametric generator," Opt. Lett. 23, 1886-1888 (1998)