Nonlinear optical properties of zinc-doped lithium niobate crystals

An investigation was made of the linear and nonlinear optical properties of LiNbO₃:Zn crystals grown from congruent melts characterized by a wide range of dopant impurity concentrations. The composition dependences of the optical properties were found to be nonmonotonic and a strong suppression of photorefraction was observed at a molar zinc concentration in excess of 6%. Crystals containing more than 6% Zn were characterized by a 47% efficiency of generation of the second harmonic of YAG:Nd³⁺ radiation.