Laser damage formation in KTiOPO4 and KTiOAsO4 crystals: Grey tracks

The grey track effect in KTiOPO4 and KTiOAsO4 is shown to be related to the presence of Ti+3. The susceptibility to grey track formation was maximum in crystals grown from tungsten-based solvents. The data shows that no clear correlations exist between grey track susceptibility and either ionic conductivity or crystal-growth temperature. The similarity of grey tracks with photorefractive damage in LiNbO3 suggests the effect can be eliminated by stabilization of Ti+3 using charge compensation.