An intracavity critically phase-matched optical parametric oscillator (OPO) was demonstrated with a LiNbO3 crystal placed inside the resonator of a diode side-pumped Q-switched Nd:YAG laser. The OPO acted as a singly resonating cavity on the signal with a threshold below 10 MW/cm2. Output energy as high as 640 µJ was observed at the idler wavelength of 3.7 µm, which corresponds to a conversion efficiency of 1.8% from diode light to idler light. Tunability over the wavelength range 3.3-4.15 µm was obtained by rotation of the LiNbO3 crystal.
© 1996 Optical Society of America
R. Lavi, A. Englander, and R. Lallouz, "Highly efficient low-threshold tunable all-solid-state intracavity optical parametric oscillator in the mid infrared," Opt. Lett. 21, 800-802 (1996)