Near-stoichiometric copper-doped lithium niobate crystals are fabricated by in-diffusion of thin layers of evaporated copper and a subsequent vapor transport equilibration treatment. The crystals are heated in a Li-rich atmosphere to increase the Li content. To determine the photorefractive properties, holographic as well as electrical measurements are performed. Saturation values of the refractive-index changes ⌬n S , bulk photovoltaic current densities j phv , photoconductivities ph , and holographic sensitivities S are measured for light intensities up to 10 4 W/m 2 . Comparison with experimental data of congruent crystals indicates that the specific photoconductivity is 15 times larger after a vapor transport equilibration treatment. The specific bulk photovoltaic coefficient ␤* is 2 times larger, refractive-index changes are 7 times smaller, and the holographic sensitivity is up to 4 times larger.

We investigate optical damage effects and coercive fields of LiTaO3 crystals and show that these properties may be tailored for applications in nonlinear optics by Mg doping and vapour transport equilibration treatments. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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