Low-threshold cw optical parametric oscillators pumped by external-cavity single-mode diode lasers

Summary form only given. Continuous wave optical parametric oscillators (OPOs) pumped directly by single-mode diode lasers are potentially compact, widely tunable spectroscopic sources in the near- to mid-infrared. Such devices based on periodically poled LiNbO/sub 3/ (PPLN) have been demonstrated, with thresholds as low as 16 mW being readily pumped by single-mode diodes. However, frequency stability of solitary Fabry-Perot diodes is generally poor and attempts to stabilize OPOs pumped by such diodes have previously been restricted by pump mode-hopping, limiting single-mode OPO operation to periods of around one minute.