| In this paper, Zn:LiTaO3 single crystals were grown by the Czochraski method using intermediate frequency heating, and as-grown boules had no macroscopic and had good optical homogeneity.X-ray powder diffraction experiment showed that the Zn:LiTaO3 crystals held the same lattice structure as the congruent sample. In Zn:LiTaO3 crystals, calculation results of unit cell parameters indicated that the lattice constant increased with the ZnO concentration increasing. Curie temperature of the Zn:LiTaO3 crystals was obtained from DTA measurement, which increased with ZnO concentration increasing when ZnO concentration was below the threshold concentration. When ZnO concentration reached the threshold concentration, the Curie temperature began to decrease.The change mechanism of the UV-V absorption edge and the IR absorption peak was also discussed in the Zn:LiTaO3 single crystals. Analysis showed Zn2+ ions took priority of replacing anti-site Ta ( TaL 4i+), firstly. When the ZnO concentration reached the threshold concentration, all of the TaL 4i+ ions were completely replaced, and Zn2+ ions began to occupy the normal Li and Ta sites simultaneously, thus formed self-compensation defect structure, ( Zn 3T-a+3 Zn L+i).The photorefractive properties of the Zn:LiTaO3 crystals, e.g., diffraction efficiency, photorefractive response time, were obtained by two-beam coupling experiment. With the ZnO concentration increasing, diffraction efficiency and erasure time decreased, the photorefractive response speed increased.The light scattering resistance of the Zn:LiTaO3 crystals was studied by the transmission facula distortion method. When the ZnO concentration was below threshold concentration, the light scattering resistance of samples showed no obviously change. In contrast, when the ZnO concentration reached threshold concentration, the light scattering resistance of samples increased significantly. It is two orders of magnitude higher than that of pure LiTaO3 crystals.
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