A comprehensive phononics of phonon assisted energy transfer in the Yb3+ aided upconversion luminescence of Tm3+ and Ho3+ in solids

The theory of phonon assisted energy transfer is being widely used to explain the Yb3+ ion aided normal and upconversion emission of various rare earth ions in different Yb3+ co-doped solids. The reported phonon dynamics in many of these studies are either incomplete or erroneous. Here we report Yb3+ aided upconversion luminescence properties of Tm3+ and Ho3+ in (Yb3+/Tm3+) and (Yb3+/Ho3+) co-doped two BaO-tellurite glasses and explain their phononics in the light of Dexter׳s theory by proposing a comprehensive scheme. The approach is valid for other systems of different phonon structures.