Optimized blue light generation in optically contacted walk-off compensated RbTiOAsO4 and KTiOP1-yAsyO4

We study type II 1.32 mu m second harmonic generation (SHG) in a RbTiOAsO4 optically contacted walk-off compensated device. The reduction of the effec tive walk-off angle by a factor of 3.7 with respect to KTiOPO4 for the same interaction leads to an enhancement by a factor of 10 of the conversion ef ficiency. A model is proposed for both type I and type II SHG in such a str ucture. The angular tuning curve is a multi-peaked one, as predicted by the model. The enhancement of the SHG conversion efficiency allows us to optim ize the generation of blue laser light at 440 nm: a specially designed KTiO P0.98As0.02O4 solid solution crystal achieves angular non-critical phase ma tching at room temperature for type II sum frequency generation 1.32 mu m 0.66 mu m --> 0.44 mu m. (C) 1999 Elsevier Science B.V. All rights reserve d.