Abstract

Continuous-wave optical parametric oscillators (cw OPOs) represent versatile sources of tunable coherent light in spectral regions inaccessible to conventional lasers. In the singly resonant (SRO) configuration, where only one of the generated waves is resonated in the optical cavity, the development of these devices has been traditionally hampered by high operation threshold (typically several watts). This has for many years prevented the widespread development of cw SROs using conventional external pumping approaches. The advent of PPLN with high nonlinearity (d_eff ~ 17 pm/V) and long interaction lengths (up to 50 mm) has enabled the realisation of external cw SROs using high-power solid-state lasers,¹ or specialist high-power semiconductor lasers.² However, the SRO power threshold in these systems still remains beyond the capability of the most commonly available laser pump sources.

© 2002 Optical Society of America