Electro-optic properties of indium/erbium-codoped lithium niobate crystal for integrated optics

Electro-optic (EO) property of In3+/Er3+-doped LiNbO3 crystal has been studied. The results show that In3+/Er3+ codoping does not cause change of clamped and unclamped EO coefficients γ13 and γ33, and the coefficient can be regarded as identical in the studied In3+ concentration range of 0-2.6 mol% (in crystal) within the experimental error of 3%. The little doping effect is desired in light of the electro-optic application of the crystal. A qualitative, comprehensible explanation for the little effect is given on the basis of the EO coefficient model of LiNbO3 and doping effect on the defect structure of LiNbO3.231