Down conversion luminescence of Tb 3+–Yb 3+ codoped SrF 2 precipitated glass ceramics

Abstract

In the Tb 3+–Yb 3+ codoped glass ceramics with SrF 2 nanocrystals precipitated, the energy transfer mechanism from Tb 3+ to Yb 3+ was investigated. The excitation power dependence of emission intensity study showed that the quantum cutting occurs during the energy transfer from Tb 3+ to Yb 3+ with the excitation of Tb 3+ high energy level. However, the one-photon process is the main reason that is responsible for the Yb 3+ infrared emission. The external quantum yields of Tb 3+ and Yb 3+ were evaluated by using an integrating sphere measurement system with the excitation of 377 and 488 nm lasers, which are much lower than the expected quantum efficiencies calculated from Tb 3+ lifetimes. The external quantum yields in the glass ceramics and as-made glasses were also compared.