Diode-pumped continuous-wave widely tunable optical parametric oscillator based on periodically poled lithium tantalate

We report on a diode-laser pumped cw optical parametric oscillator (OPO) based on quasi-phase-matched periodically poled lithium tantalate. Pumped by the 2.3-W single-frequency, nearly diffraction-limited 925-nm output of an InGaAs diode master-oscillator power amplifier, the pump and signal resonant OPO generates a single-frequency idler wave with an output of as much as 244 mW. The wavelengths of the signal and idler waves are widely tunable in the range $1.55–2.3 \mathit{\mu }\mathrm{m}$ by use of different poling periods (27.3 to $27.9 \mathit{\mu }\mathrm{m}$) and by variation of the crystal temperature in the range 70–190 °C.