Influence of Hf4+ ions concentration on the defect structure and exposure energy in Hf:Ho:LiNbO3

A series of Hf:Ho:LiNbO3 crystals with various levels of HfO2 doping were grown by the conventional Czochraski technique. The measurement of the Hf and Ho concentrations in the crystals was carried out with an inductively coupled plasma atomic emission spectrometer (ICP-OE/MS). The infrared (IR) spectrum was measured in order to analyze the defect structure of the crystals. The light-induced scattering was characterized quantitatively via the incident exposure energy. The results showed that the ability to resist the light-induced scattering was improved considerably with the increase in concentration of Hf4+, however, light-induced scattering resistance ability weakened as the concentration of Hf4+ surpasses the concentration to 8 mol%. The relationship between the defect structures and the light-induced scattering was discussed.

► Hf:Ho:LiNbO3 crystals were grown at different HfO2 doping concentrations.
► Distribution coefficients of Hf and Ho ions decrease as Hf4+ increases.
► Light-induced scattering of Hf (6 mol%):Ho:LiNbO3 can be improved considerably.