Electrooptic and ferroelectric properties of lithium tantalate single crystals as a function of melt composition

Abstract

Electrooptic, electric, ferroelectric and optical properties of lithium tantalate single crystals are investigated as a function of the melt composition for Li-Ta mole ratios ranging from 0.8 to 1.2. The Curie temperature depends on the melt composition, but the dependence is not linear. Specific resistivity increases as Li concentration in the melt increases. Homogeneity of the natural birefringence becomes higher with increasing Li concentration. Optical loss decreases in crystals grown from Li-rich melts. The crystals become much more resistant to optical damage after annealing in an oxygen atmosphere at about 1000°C.