Defect Structures and Densities of Mg-Doped Lithium Niobate

Two sets of defect structure models formed in Mg:LiNbO3 varying with the Mg concentration are proposed. In order to determine the defect models, the density of a group of Mg:LiNbO3 crystal samples doped with different Mg concentration is measured. The density of the crystals are also calculated by using the defect models. The calculated results show that the defect structure models of set 2 are in good agreement with the experimental results. It is further predicted by the calculation that the critical Mg concentration of the Mg-doping level threshold effect for congruent Mg:LiNbO3 should be 5.30 mol%.