UV laser-induced damage tolerance measurements of CsB3O5 crystals and its application for UV light generation

Abstract Cesium triborate, CsB 3 O 5 (CBO), is an excellent nonlinear optical crystal for ultraviolet light generation. CBO crystals can be grown by top seeded solution growth from self flux solutions. The growth of large-size crystal is difficult because of the multi-nucleation and dissolution of seed during growth. These problems have been avoided and large size crystals (159.2 g) of size 50 × 45 × 45 mm 3 ( a  ×  b  ×  c ) have been grown. The bulk laser-induced damage threshold (LIDT) of CBO was determined using an 1-on-1 technique by the third-harmonic (355 nm) light of longitudinal single-mode Q-switch Nd:YAG laser. The bulk LIDT was found to be two times that of fused quartz for a 6 ns pulse. The as-grown CBO crystal has been used to generate the highest ever reported third-harmonic power of 103 W for the case of a single-pass frequency-conversion system using a high-power Nd:YAG laser.