Luminescence properties of nominally pure and doped lithium niobate crystals grown by different technologies

The dependence of photoluminescence of nominally pure and Zn (Mg)-doped lithium niobate crystals on composition, kind, concentration of doped element and doping technology, was observed. The photoluminescence did not depend on doped element kind and was decreased with increasing in stoichiometry. A decrease in the luminescence of NbNb–NbLi centers was observed in weakly Zn (Mg)-doped LiNbO3 crystals, the emission of NbNbO6 groups dominated in strongly ones. LiNbO3 : Zn (Mg) crystals obtained by homogeneous doping had the emission of both NbNb — NbLi centers and NbNbO6-groups.