The optical properties of LiNbO3 single crystals obtained in air atmosphere

Single crystals of LiNbO3 were grown by the Czochralski technique in an air atmosphere. The critical diameter and the critical rate of rotation were calculated. X-Ray measurements of the powder were carried out to obtain the lattice parameters. The optical constants were calculated by Kramers-Kronig analysis of reflectance data. The optical properties of LiNbO3 single crystals were studied for samples grown in an air atmosphere to investigate the influence of air on the optical properties of the formed crystals. A peak due to OH- gtroups appears in the transmission spectrum at 3385 cm-1. It was still present after annealing in an air atmosphere at temperature up to 873 K, but it was no longer detectable after annealing at 1473 K in an electric field. Thick films of the high-temperature superconductor YBa2Cu3O7 (Ag) were obtained on plates of LiNbO3 single crystals. The obtained results are discussed and compared with published data.