Growth of large-diameter nearly stoichiometric lithium niobate crystals by continuous melt supplying system

A melt supplying double crucible technique was described. Nearly stoichiometric lithium niobate (NSLN) crystals were grown in a lower crucible with a melt composition of [Li2O]/[Nb2O5]=58/42, and the melt was continuously added from a higher crucible. The composition of the adding melt was [Li2O]/[Nb2O5]=36/64, far away from the stoichiometric point of 50/50. NSLN crystals of 3 in. were successfully grown, and the average concentration of Li2O was 49.85 mol% with a radial composition deviation of ±0.02 mol% and an axial composition deviation less than ±0.03 mol%/cm.