Ternary system Li2O-K2O-Nb2O5

Growth conditions of stoichiometric or near-stoichiometric lithium niobate (sLN) from K2O containing fluxes have been studied by investigating phase equilibria in the ternary system Li2O-K2O-Nb2O5. The crystallization area of LiNbO3 was confirmed by growth experiments on the g1 (LiNbO3-K2O), g2 (LiNbO3-ternary eutectic liquid (Et: 45.0 ± 1.5 mol% Nb2O5, 26.0 ± 1.5 mol% K2O and 29.0 ± 1.5 mol% Li2O)) and g3 (LiNbO3-KNbO3) joins. The yield and the composition of LiNbO3 single crystals were tested for a wide range of starting compositions. From these experiments, the starting compositions leading to stoichiometric lithium niobate have been determined.