Efficient Er3+:4I11/2 → 4I13/2 radiative transition regulated by optimizing the sensitization mechanism.

A series of fluorophosphates glass codoped with active Er3+ ions and sensitizing ions of different systems were prepared to systematically study their sensitization effect in order to obtain efficient MIR luminescence. Differential scanning calorimetry curve indicates the favorable thermal stability of the glass host. A comprehensive analysis of the sensitization mechanism is given based on the synthesis considering the position and intensity of fluorescence emissions together with the lifetime of Er3+:4I13/2 active level. The results show two positive sensitization effects: the eliminating effect to the lower laser level of Er3+ active ions represented by Pr3+ ions reducing the lifetime of 4I13/2 energy level to a great extent; and improving the absorption efficiency of pumping source sensitized by Yb3+ ions. The paper has provided a mental knowledge for sensitization mechanism in rare earth multi-doped materials together with the aiming of promoting the MIR luminescence of Er3+ ions.