Spectroscopic properties of Er3+:4I13/2→4I15/2 transitions
in erbium-doped bismuth-borate glasses with composition of
45Bi2O3–35B2O3–10GeO2–10Na2O have been investigated as a
function of Er3+-doped concentration. The results show that the
fluorescence decay of Er3+ becomes faster and deviates from the
single exponential behavior due to the energy transfer from Er3+
to OH− groups under the low Er3+-doped case. When the Er2O3
content exceeds 1.0mol%, the migration-induced energy transfer
among Er3+ ions dominates the energy-transfer rate and the
1.53_m fluorescence intensity of Er3+ decreases due to concentration
quenching effect. The above research results indicate that
an appropriate Er3+ concentration may be doped to achieve high
intensity and broad emission, and a reducing OH− groups drying
procedure may be adopted to enhance radiative transition for further
development of Bi2O3–B2O3–GeO2–Na2O glass with excellent
spectroscopic properties applied for broadband fiber amplifier.