Determination of the Li/Nb ratio in LiNbO3 crystals grown by Czochralski method with K2O added to the melt

Off-congruent lithium niobate single crystals were grown by the Czochralski method with K2O added to the congruent melts in a concentration varying be tween 2 and 10.5 wt%. The Li/Nb ratio was determined by means of indirect m ethods such as the fundamental absorption edge positon. the IR vibrational spectrum. lattice parameters and the variation of the refractive indices. T he data presented in this work show that the Li/Nb ratio can be controlled by the amount of K2O added to the congruent melt. Moreover. the techniques employed For characterization are good tools for the determination of the L i/Nb ratio. (C) 2000 Elsevier Science B.V. All rights reserved.