Single-mode, singly resonant, pulsed periodically poled lithium niobate optical parametric oscillator

We report single longitudinal mode operation of a pulsed Nd:YAG pumped peri odically poled lithium niobate optical parametric oscillator (OPO). The com bination of a prism and an etalon provides both coarse and fine spectral re solution, thereby eliminating parasitic resonant oscillation of cascaded si gnal wavelengths, idler wavelengths, and adjacent longitudinal modes of the signal field. Optical bandwidths of less than 300 MHz have been obtained a t signal wavelengths between 1.47 and 1.59 mu m. In comparison with broadba nd operation, the single-mode OPO shows only a 9% reduction in pump depleti on with a negligible reduction in extraction efficiency. (C) 1999 Optical S ociety of America OCIS codes: 190.4360, 190.4410, 190.4970, 230.4320.