Crystal Growth and Optical Characterization of Rare-Earth (Re) Calcium Oxyborate ReCa 4O(BO 3) 3 (Re = Y or Gd) as New Nonlinear Optical Material

We report on the growth of GdCa 4 O(BO 3 ) 3 (GdCOB) and YCa 4 O(BO 3 ) 3 (YCOB) crystals and their characterization as new nonlinear optical materials. The crystals with good optical quality were grown by the Czochralski method. YCOB, the characteristics of which has not previously been reported to our knowledge, has a larger temperature acceptance bandwidth than that of GdCOB, and third harmonic generation of a Nd:YAG laser in this crystal was demonstrated.