Highly Efficient Third Harmonic Generation in a Periodically Poled MgO:LiNbO3 Disk Resonator

High-efficiency generation of the third harmonic of 1.55 mu m light is observed in a periodically poled MgO-doped LiNbO3 disk resonator. The second harmonic is simultaneously generated. The blue-green emission arises from cascaded parametric processes of second-harmonic and sum-frequency generation by whispering gallery modes. An external conversion efficiency of 1.5%/W-2 is obtained. (C) 2009 The Japan Society of Applied Physics DOI: 10.1143/APEX.2.122401