The effect of MgO doping on optical properties of LiNbO3 single crystals

Undoped and MgO doped Lithium niobate single crystals were grown by the Czochralski technique. Comparative study of the optical properties of undoped and 7 mol% MgO doped LiNbO3 crystal was undertaken. The effect of doping on refractive indices as well as second harmonic generation has been experimentally analyzed. The results of the polarization characteristics of second harmonic generation (SHG) support the major contribution of Li–O bonds to optical nonlinearity. MgO doping reduces the number of localized excitons and the grown LiNbO3 crystal approaches the stoichiometric composition. This causes blue shift in the absorption edge of the crystals.