16.6W, continuous-wave, Yb-fiber-Laser-Pumped, singly-resonant optical parametric oscillator based on MgO:PPLN

Using the out-coupling approach, an output power of up to 16.6 W (8.3 W of signal and 8.3 W of idler) from a cw singly-resonant optical parametric oscillator (SRO) for 26.8 W of pump power at an extraction efficiency to 62% is generated . The device is based on an Yb fiber laser pump, resulting in a highly compact, practical, and portable design. The Yb fiber pump laser delivers up to 30 W of single-frequency radiation at 1064 nm in a linearly polarized beam with M² factor < 1.01. The pump laser is operated at maximum power and an attenuator comprising a half-wave plate (HWP) and a polarizing beam splitter is used to vary the input fundamental power.The SRO is based on a 50-mm long multi-grating (Lambda = 29.5-31.5 m) MgO:PPLN crystal (HC Photonics) and is configured in a compact ring cavity consisting of two plano-concave mirrors, M₁ and M₂ (r = 150 mm) and two plane mirrors M₃,M₄. Results on wavelength tuning and further enhancement of output power using optimum output coupling is also presented.