Continuous-wave optical parametric oscillator pumped by a fiber laser green source at 532 nm

We report a high-power, cw, singly resonant optical parametric oscillator (SRO) using a simple, compact fiber pump laser architecture in the green. The SRO, based on MgO:sPPLT, is pumped by 9.6 W of single-frequency cw radiation at 532 nm obtained by single-pass second-harmonic generation (SHG) of a 30 W Yb fiber laser, also in MgO:sPPLT. Using two identical crystals of 30 mm length for SHG and SRO, we generate cw idler powers of up to 2 W over 855-1408 nm, with a peak-to-peak power stability <11.7% over 40 min, in a TEM00 spatial mode with M-2 < 1.26. Using finite output coupling of the resonant wave, we extract 800 mW of signal power with peak-to-peak power stability <10.7% over 40 min, and a frequency stability < 75 MHz over 15 min. The signal and idler output have TEM00 beam profile with M2 < 1.52 across the tuning range. (C) 2009 Optical Society of America