Alkali metal oxide solvents in the growth of stoichiometric LiNbO3 single crystal

X2O (X=Na, K, Rb, Cs) solvents were studied for the flux growth of stoichiometric LiNbO3. All alkali metal oxide solvents decrease the crystallization temperature of LiNbO3 as compared to that using the conventional melt growth technique. The properties of crystals grown from K2O, Rb2O and Cs2O fluxes were found to be similar, but constant stoichiometric composition can only be reached using K2O solvent, whereas the properties of the crystals grown from Na2O flux are quite different since Na enters the lattice.