Gd1−xYxCa4O (BO3)3 (GdYCOB) crystal operating at raised temperature suppressed photo-induced damages such as photorefractive damage and gray-track in noncritically phase-matched third-harmonic generation of Nd:YAG lasers. We have investigated the dependence of photo-induced damage tolerance on the growth atmosphere in GdYCOB. It was found that the crystal grown in the air had more than three times higher tolerance of gray-tracking than that grown in Ar atmosphere. It is shown that gray-track was related to oxygen defects in the crystal.
© 2001 Optical Society of AmericaPDF Article