Continuous-wave, singly-resonant, optical parametric oscillator based on periodically poled KTiOPO/sub 4/

Summary form only given. The enhanced effective nonlinearity of quasi-phase-matched materials, most notably that of periodically poled LiNbO/sub 3/ (PPLN), has placed once prohibitively-high oscillation thresholds of externally-pumped continuous-wave (CW) SROs within the domain of diode-pumped solid-state lasers. More recently, the use of PPLN has enabled the development of SROs with unprecedently low thresholds in the intracavity configuration. Practical utilisation of more recently developed poled nonlinear materials such as periodically poled RbTiOAsO/sub 4/ (PPRTA) and periodically poled KTiOPO4 (PPKTP), with lower effective nonlinearities places a more rigorous power demand on the pump laser source. We have recently demonstrated an intracavity pumping regime to address the higher SRO oscillation thresholds of devices based on PPRTA and conventional birefringent materials KTP and KTA. Herein we describe the room-temperature operation of a CW intracavity SRO based on PPKTP.