Defect structure and increased photorefractive damage resistance of ZnO highly doped congruent LiNbO3:Ho:Yb single crystals

The congruent ZnO highly doped LiNbO3:Ho:Yb:Zn crystals has been grown by the Czochralski methold. The IR transmission and UV-Vis absorption spectrum were determined and discussed the defect structure of LiNbO3:Ho:Yb:Zn crystals. The photorefractive damage resistance ability of LiNbO3:Ho:Yb:Zn crystals is studied by both of the Sénarmont compensation method and the transmitted beam pattern distortion method. The saturated value of the birefringence change of LiNbO3:Ho:Yb:Zn (9 mol%) crystal is 0.82×10−5, which is six times smaller than that of congruent pure LiNbO3 crystal. The results of UV-Visible absorption, IR transmission spectra and photorefractive damage experiments of LiNbO3:Ho:Yb:Zn crystals are coherent and availably notarize that the photorefractive damage resistance threshold concentration of the Zn2+ ions doped in LiNbO3:Ho:Yb crystals is about 7 mol% in the melt.