Study of the nonlinear optical properties of 7.5 mol% Nb:KTP crystals

Sellmeier's equations and the equations for the thermal principal refractive index coefficients as a function of wavelength fur 7.5 mol% Nb:KTP crystals are presented. Based on these equations, the nonlinear optical parameters for 7.5 mol% Nb:KTP crystals, especially the angular, spectral, and temperature acceptance bandwidths, are calculated. By comparing these results with KTP and KNbO/sub 3/ crystals, 7.5 mol% Nb:KTP crystals show better performance than KNbO/sub 3/ crystals in generating blue coherent light by direct second-harmonic generation of a semiconductor diode laser.