High-Beam-Quality Continuous Wave 3 W Green-Light Generation in Bulk Periodically Poled MgO:LiNbO3

Continuous-wave 3 W green-light generation at 542 nm is reported in bulk periodically poled MgO:LiNbO3 using single-pass frequency doubling of a Yb-doped fiber laser operating at 1084 nm. The Yb-doped fiber laser had an output power of 9 W, single polarization, beam quality factor M2~1.05, and a spectrum bandwidth of 0.07 nm. MgO:LiNbO3 samples of 1.0 mm thickness, 25 mm interaction length, and 7.38 µm domain period were fabricated by using a high-voltage multi pulse poling method. A maximum green power of 3 W with a 34% infrared-to-green conversion efficiency and a 6%/W normalized conversion efficiency was obtained. In addition, the generated green light possessed beam quality factor (M2) of less than 1.1 and an output stability of 1.5%.