Improvement Of Er3+:I-4(11/2)-> Ce3+:F-2(5/2) Energy Transfer Rate In Er3+/Ce3+ Co-Doped Teo2-Zno-Na2o-Nb2o5 Glasses

The B2O3 component was introduced into Er3+/Ce3+ co-doped TeO2-ZnO-Na2O-Nb2O5 glass to improve energy transfer rate of Er3+:I-4(11/2)-> Ce3+:F-2(5/2) phonon-assisted cross-relaxation process. With the 6 mol% substitution of B2O3 for TeO2, the energy transfer rate increased from 1300 to 1831 s(-1) and the fluorescence intensity increased by about 13.4%. However, the more B2O3 substitution in the same glass system reduced the quantum efficiency of Er3+:I-4(13/2)-> 4I(15/2) transition due to the higher OH- group concentration. The results show that an appropriate amount of B2O3 component can be used to improve the phonon-assisted energy transfer rate and enhance 1.53 mu m fluorescence emission by increasing the phonon energy of host glass. The effect of B2O3 On the energy transfer process, the lifetimes of the 4I(11/2) and I-4(13/2) levels, and the upconversion emission have also been investigated. (C) 2008 Published by Elsevier B.V.