Stimulated Polariton Scattering in LiNbO3 Based Optical Parametric Oscillators

We report a high power single-frequency continuously tunable mid-infrared (MIR) singly resonant optical parametric oscillator (SRO) using 80-mm-long MgO-doped PPLN (MgO:PPLN) crystal pumped by a continuous-wave Yb-fiber laser. The SRO is tun-able in MIR band of 3760–3970 nm giving maximum 1.8 W power at 3895 nm. We observed signal side-bands which could be attributed to the process of stimulated polariton scattering.