Temperature dependence of luminescence behavior in Er/Yb co-doped transparent phosphate glass ceramics

The effect of temperature on the luminescence intensity of up-conversion and near infrared in Er³⁺/Yb³⁺ co-doped phosphate glass ceramics has been investigated. Efficient green and red up-conversion luminescence and strong infrared fluorescence at 1.54 μm wavelength are observed under excitation of 975 nm. The fluorescence intensity is changing at different temperature and the results are explained with the level transitions in Er³⁺/Yb³⁺ co-doped system. Meanwhile, the lifetime of Er³⁺:⁴I_13/2 level corresponding to different operating temperature and pump power is also discussed, and the experimental results are fitted using multiphonon relaxation theory.