Wavelength dependence of electro-optic effect in paraelectric potassium sodium tantalate niobate single crystal

摘要

The refractive indices and quadratic electro-optic effect in terms of the coefficients (R_(11)-R_(12)) in a paraelectric K_(0.95)Na_(0.05)Ta_(0.58)Nb_(0.42)O_3 single crystal were measured. The dispersion of the refractive index was described exactly by a single-term Sellmeier equation. We found an obvious dispersion of the electro-optic coefficients (R_(11)-R_(12)), and the coefficients decreased quickly with increasing wavelength above the Curie temperature. Following [J. Appl. Phys. 40, 720 (1969)], we obtained a dispersion equation for the electro-optic effect in a paraelectric potassium sodium tantalate niobate single crystal. The experimental results agreed well with the dispersion model.