Explorations of new types of second-order nonlinear optical materials in Cd(Zn)-V^v-Te^IV-O systems

Solid-state reactions of zinc(II) or cadmium(II) oxide, V₂O ₅, and TeO₂ at high temperature led to two novel quaternary compounds, namely, Zn₃V₂TeO₁₀ and Cd₄V₂Te₃O₁₅. The structure of Zn₃V₂TeO₁₀ is a complicated three-dimensional (3D) network constructed by the interconnection of ZnO₅, ZnO ₆, VO₄, and TeO₄ polyhedra via corner- and edge-sharing. Cd₄V₂Te₃O₁₅ with an acentric structure features a 3D network in which the cadmium tellurite layers are further interconnected by both "isolated" VO₄ tetrahedra and one-dimensional (ID) vanadium oxide helical chains. Cd ₄V₂Te₃O₁₅ displays a second harmonic generation (SHG) efficiency of about 1.4 times that of KH₂PO ₄ (KDP). Both compounds are direct band-gap semiconductors and are transparent in the range of 0.6-10.0 μm. Measurements of luminescence indicate that both compounds exhibit broad emission bands in the blue-light region.