Up-conversion of Nd^(3+)/Yb^(3+)/Tm^(3+) tri-doped CaTeO3 compound under excitation of 808 nm

摘要

Nd^(3+)/Yb^(3+)/Tm^(3+) tri-doped CaTeO3 compounds were prepared by a solid-state reaction method.Bright blue up-conversion(UC) luminescence at around 476 nm,which corresponds to the Tm^(3+):^(1)G_(4)→^(3)H_(6) transition,was observed under 808-nm excitation.The Nd^(3+)→Yb^(3+)→Tm^(3+) energy transfer process was responsible for the strong blue up-conversion emission in the tri-doped phosphor.The Tm^(3+) blue up-conversion emission intensity was strongly dependent on the concentrations of Yb^(3+) and Nd^(3+).The possible up-conversion mechanisms for the Nd^(3+)/Yb^(3+)/Tm^(3+) tri-doped CaTeO_(3) phosphor are discussed,based on the Nd^(3+) and Yb^(3+) concentration-dependent UC spectra,near-infrared luminescence spectra and luminescence decay curves.