Continuous-wave singly-resonant optical parametric oscillator with resonant wave coupling.

We report major enhancements in the overall performance of continuous-wave singly-resonant optical parametric oscillators (cw SROs) through finite output coupling of the resonant wave. Using a cw SRO based on MgO:sPPLT pumped at 532 nm, we demonstrate improvements of 1.08 W in total output power, 10% in total extraction efficiency, and a 130-nm extension in the useful tuning range, while maintaining pump depletions of 70%, idler output powers of 2.59 W, and a minimal increase in oscillation threshold of 24%. The output-coupled cw SRO can deliver a total power of up to 3.6 W at 40% extraction efficiency across 848-1427 nm. The single-frequency resonant wave also exhibits a higher spectral purity than the non-resonant output.