Effect of silver nanoparticles on the 1.53 mu m fluorescence in Er super(3+)/Yb super(3+) codoped tellurite glasses

Improving the spectroscopic properties of rare earth (RE) doped glass materials is a challenging task. In the present work the metallic silver nanoparticles (Ag NPs) were embedded into Er super(3+)/Yb super(3+) codoped tellurite glasses with composition TeO sub(2)-Bi sub(2)O sub(3)-TiO sub(2 ), prepared using melt-quenching and subsequent heat-treated techniques, and the improved effect of Ag NPs on the 1.53 mu m band fluorescence of Er super(3+) ions was investigated. About 24 h heat-treatment of Er super(3+)/Yb super(3+) codoped tellurite glass containing 1 mol % amount of AgNO sub(3) at the temperature 370 degree C yielded the well-dispersed and near-spherical Ag NPs with similar to 11.4 nm average diameter as evidenced by transmission electron microscopy (TEM) image. The intense 1.53 mu m band fluorescence was observed in the prepared Er super(3+)/Yb super(3+) codoped tellurite glasses under the excitation of 980 nm and was further improved with the presence of Ag NPs in the glass matrix, which is attributed to the enhanced local electric field around doped RE ions induced by Ag NPs and the possible energy transfer from Ag NPs to Er super(3+) ions. The enhanced local electric field was well demonstrated by comparing the variation of emission spectra of hypersensitive probe Eu super(3+) ions in tellurite glasses with and without Ag NPs. From the Judd-Ofelt analysis, it was also found that the value of Omega sub(6) Omega 6 intensity parameter increased slightly with the increase of Ag NPs concentration in a certain range, also confirming the possibility of realizing strong fluorescence emission. In addition, the amorphous structural nature was demonstrated by the measured X-ray diffraction (XRD) patterns with no sharp diffraction peak. The enhanced 1.53 mu m band fluorescence indicates that the Er super(3+)/Yb super(3+) codoped tellurite glass with an appropriate amount of Ag NPs is a promising candidate for the development of Er super(3+)-doped fiber amplifiers (EDFAs) applied in the WDM systems.