SELF-FREQUENCY DOUBLING IN ND,SC2O3LINBO3 AT ROOM-TEMPERATURE

Self-frequency doubling is reported in a Nd,Sc2O3:LiNbO3 single crysta l. The SC2O3 doping produced room-temperature (20-degrees-C) 90-degree s noncritical phase matching (theta = 90-degrees-C). Under quasi-cw co nditions, 0.14 mW of frequency-doubled 546-nm radiation was produced. The pump-to-green-light conversion efficiency was 11%/W with a 25-mW a bsorbed input power lasing threshold. Only the fundamental 1092-nm s-p olarized oscillation was produced, rather than the p-polarized output, as reported for Nd,MgO:LiNbO3. This simplified the cavity by eliminat ion of the Brewster window needed to force the s-polarized output requ ired for type I phase matching.