a b s t r a c t
Spectroscopic properties of Er3+:4I13/2→4I15/2 transitions in erbium-doped bismuth-borate glasses with
composition of 45Bi2O3–35B2O3–10GeO2–10Na2O were investigated. The results show that the fluorescence
intensity reveals a nonexponential decaying behavior for glasses with lowEr3+-dopedconcentration.
It is ascribed to the energy transfer from Er3+ to OH− groups, and the energy-transfer microparameter
CEr–OH is about 33.1×10−40 cm6 s−1 in Er2O3-doped content of 0.1 mol% glass. Whereas an exponential
behavior is dominant for glasses with high Er3+-doped case. Nonradiative decay in the latter is mainly
originated from the energy migration among Er3+ ions, and this energy migration is also responsible for
the concentration quenching of 1.53mfluorescence emission. The interaction microparameter CEr–Er for
the migration among Er3+ ions was calculated to be an average of 43.9×10−40 cm6 s−1. Meanwhile, the
radiation trapping of Er3+ leads to the effective emission width broadening from 66.3 to 82.5nm with
Er2O3 doped content increased from 0.1 to 3.0 mol%.