Recent advances of YCOB family nonlinear optical crystals

We have recently developed NLO crystals, the YCOB family, and found that Gd/sub x/Y/sub 1-x/Ca/sub 4/O(BO/sub 3/)/sub 3/ (GdYCOB) is noncritically phase-matchable (NCPM) for third- and second-harmonic generation (THG, SHG) of a Nd:YAG laser at room temperature. Here, the NLO properties for THG and SHG are reviewed and discussed in relation to those of other nonlinear optical crystals such as LBO and KH/sub 2/PO/sub 4/ (KDP).