Nanosecond laser induced damage in RbTiOPO4: the missing influence of crystal quality.

Nanosecond laser induced damage in RbTiOPO(4) (RTP) an isomorphic material to the more widely known KTiOPO(4) (KTP) is studied in crystals with varying properties. The ionic conductivity along the z-axes of the tested crystals ranged from 1.5 10(-9) S/cm to 1.1 10(-12) S/cm. Further, different growth sectors with different absorption in the range of hundreds of ppm/cm and differing zones in inhomogeneous crystals have been investigated. Despite these important differences in crystal quality, no significant difference could be observed in the laser damage resistance at 1064 nm. Thus growth induced defects only play a minor role in nanosecond laser induced damage in RTP. Transient, laser induced defects are discussed in analogy with KTP as possible laser damage precursors.