The fluorescence properties of highly-doped erbium fluoroaluminate glass pumped at 800 and 980 nm

Abstract The fluorescence properties of 1.54 μm emission, as well as the upconversion emissions, of fluoroaluminate glasses with Er 3+ concentration up to 19.8 mol% are investigated under 800 and 980 nm excitation. As reported previously [Mater. Lett. 47 (2001) 189], strong 1.54 μm fluorescence emission is observed in Er 3+ highly-doped fluoroaluminate glass under 980 nm excitation. Compared with that excited at 980 nm, the 1.54 μm emission under 800 nm excitation is much weaker, owing to the much more upconversion channels. Upon 800 nm excitation, the upconversion emission around 550 and 660 nm can be clearly observed. The results indicate that the energy transfer process, 4 S 3/2 + 4 I 9/2 → 2 4 F 9/2 , plays a significant role for 660 nm upconversion emission in Er 3+ highly-doped fluoroaluminate glass.