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. (c) 2007 Elsevier B.V. All rights reserved.