Temperature Dependence of Emission Cross-section of Yb:glass

The temperature dependence of the emission cross-section of Yb (5 x 10(20) atoms/cm(3))-doped fluorophosphate glass has been investigated in the temperature range from 77 K to 380 K. The emission cross-section has been evaluated from the measured fluorescence spectra and the lifetime, using the Fuchtbauer-Ladenburg formula. A large change in the emission cross-section from about 0.6 x 10(-20) cm(2) at 380 K to 1.1 x 10(-20) 2 at 77 K was cm obtained by decreasing the temperature. The effect of reabsorption is found to be significant even at temperatures as low as 160 K which leads to underestimation of the emission cross-section values.