Thermal effect on up-conversion in Er3+/Yb3+ co-doped silicate glass

Er3+–Yb3+ co-doped silicate glasses with high up-conversion efficiency were fabricated. A fivefold enhancement of the up-conversion fluorescence emission at 525 and 550 nm with a temperature rising in them, excited at 970 nm, is carried out. A model is proposed to describe the experimental phenomena based on the temperature dependent multiphonon-assisted Stokes excitation and non-radiative transition theories. The thermometry range, relying on the fluorescence intensity ration method, is excessively extended due to the high vitreous transition temperature in silicate glass.