The effect of OH − groups on the spectroscopic properties of erbium-doped tellurite glasses

A series of five different concentration erbium-doped tellurite glasses with various hydroxl groups were prepared. Infrared spectra of glasses were measured. In order to estimate the exact content of OH− groups in samples, various absorption coefficients of the OH− vibration band were analyzed under the different oxygen bubbling times. The absorption spectra of the glasses were measured, and the Judd-Ofelt intensity parameters Ω i of samples with the different erbium ions concentration and OH− contents were calculated on the basis of the Judd-Ofelt theory. The peak stimulated emission cross-section of 4|13/2→4|15/2 transition of the samples was finally calculated by using the McCumber theory. The fluorescence spectra of Er3+:4|13/2→4|15/2 transition and the lifetime of Er3+:4|13/2 level of the samples were measured. The effects of OH− groups on the spectroscopic properties of Er3+ doped samples with the different concentrations were discussed. The results showed that the OH− groups had great influences on the Er3+ lifetime and the fluorescence peak intensity. The OH− group is a main influence factor of fluorescence quenching when the doping concentration of Er2O3 is smaller than 1.0 mol%, but higher after this concentration, the energy transfer of Er3+ ions turns into the main function of the fluorescence quenching. And basically, there is no influence on the other spectroscopic properties (FWHM, absorption spectra, peak stimulated emission cross section, etc.).