Enhanced photorefractive properties in Hf, Ce and Cu co-doped LiNbO3 crystals for holographic application

摘要

Hf, Ce and Cu co-doped LiNbO3 crystals with various level of Hf doping were grown in air by a conventional Cz method. The infrared spectra were measured to discuss the defect structures and the mechanism of the absorption peak shift in these crystals. The light-induced scattering of the crystals was evaluated by the transmitted light method. The influence of the Hf-doping level on the photorefractive properties of Hf, Ce and Cu co-doped LiNbO3 crystals was studied via two-beam coupling. It is found that proper doping Hf is an efficient method to enhance the comprehensive photorefractive properties of the LiNbO3. Using one of these crystals as medium, 200 holograms storage and correlation experiments based on angle fractal multiplexing have been realized in a coherent volume 0.073 cm(3). Moreover the diffraction efficiency is uniform and the storage density has reached 2.2 Gb/cm(3). (C) 2015 Elsevier B.V. All rights reserved.