Photorefractivity Vs. wavelength a comparative study of Mg- and Zr-doped Lithium Niobate crystals

In this paper, a comparison of the photorefractivity produced in Mg-doped and Zr-doped crystals as a function of the wavelength used to induce the photorefractive effect is shown.This paper shows very similar performances between Mg-doped and Zr-doped samples, even if some small differences in the wavelength dependence of photorefractivity appear, thus suggesting a different distribution of defects levels in the band-gap. This result, combined with the fact that Zr-doping allows easier waveguide realization and periodic poling (still unpublished results, manuscripts are under preparation), pushes for the development of industrial-quality large Zr-doped lithium niobate (LN) wafers, that could replace the current standards given by Mg-doped and pure congruent LN.