Singly resonant optical parametric oscillation in periodically poled lithium niobate waveguides

We report quasi-phase-matched singly resonant optical parametric oscillation in electric-field-poled lithium niobate waveguides. Parametric gains as high as 250%/W, an oscillation threshold of 1.6 W (peak), idler output powers of 220 mW, and a tuning range of 1180-2080 nm for pump wavelengths of 756-772 nm have been observed. Pump depletion is limited to 40% because of the multiple launched transverse modes at the pump wavelength. We predict that fully optimized waveguide singly resonant oscillators can have thresholds of similar to 100 mW, accessible to cw diode pumping. (C) 1997 Optical Society of America