Influence of MgO doping on spontaneous polarization and second-order susceptibility in LiNbO3 crystals

On the basis of ‘average effective electronegativity’ of A and B site in LiNbO3 crystal, the influence of MgO doping on structural and optical properties are theoretically analyzed. An empirical formula is also suggested to determine the Mg ion occupancy at A site. Present analysis suggests that the spontaneous polarization and second-order susceptibility decreases rapidly up to 4.5 mol% MgO doping while a sluggish decrease in its values is expected above this doping concentration.