Spectroscopic properties of Er3+:4I13/2 level in Bi2O3–B2O3–GeO2–Na2O glasses

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 low Er3+-doped concentration. It is ascribed to the energy transfer from Er3+ to OH− groups, and the energy-transfer microparameter CEr–OH is about 33.1×10−40cm6s−1 in Er2O3-doped content of 0.1mol% 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 1.53μm fluorescence emission. The interaction microparameter CEr–Er for the migration among Er3+ ions was calculated to be an average of 43.9×10−40cm6s−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 3.0mol%.