Continuous-Wave Deep Blue Generation in a Periodically Poled MgO:LiNbO3 Crystal by Single-Pass Frequency Doubling of a 912-nm Nd:GdVO4 Laser

Continuous-wave blue light generation at 456 nm is reported in bulk periodically poled MgO:LiNbO3 by single-pass frequency doubling of a Nd:GdVO4 laser operating at 912 nm. The Nd:GdVO4 laser had a maximum output power of 2.6 W for 15.7 W pump power, with a beam M2 factor of 1.4. MgO:LiNbO3 samples of 1.0-mm thickness and 4.2 µm domain period were fabricated by using a high-voltage multipulse poling method. A maximum blue power of 167 mW with 8.3% infrared-to-blue conversion efficiency and 4.2%/W normalized conversion efficiency was obtained. To the best of our knowledge, this is the first report on continuous-wave deep blue (below 460 nm) generation by quasi-phase matching in periodically poled MgO:LiNbO3.