Microlaser-pumped periodically poled lithium niobate optical parametric generator-optical parametric amplifier

For what is believed to be the first time, a single-longitudinal-mode passively Q -switched Nd:YAG microlaser is used to pump a narrow-bandwidth periodically poled lithium niobate (PPLN) optical parametric generator-optical parametric amplifier (OPG-OPA). Before amplification in the OPA, the output of the OPG stage was spectrally filtered with an air-spaced etalon, resulting in spectroscopically useful radiation (bandwidth, ∼0.05 cm-1 FWHM) that was tunable in 15-cm-1 segments anywhere in the signal range 6820-6220 cm-1 and the idler range 2580-3180 cm-1 . The ability to pump an OPG-OPA with compact, high-repetition-rate, intrinsically narrow-bandwidth microlasers is made possible by the high gain of PPLN. The result is a tunable light source that is well suited for use in portable spectroscopic gas sensors. (c) 2000 Optical Society of America