Investigation on Nonradiative Decay of the Er^{3+ 4}I_13/2 →⁴I_15/2 Transition in Different Tellurite Glass Matrix

Three kinds of Er³-doped tellurite glasses with different hydroxyl groups are prepared by the conventional melt-quenching method. Infrared spectra are measured to estimate the exact content of OH^- groups in samples. The maximum phonon energy in glasses are obtained by measuring the Raman scattering spectra. The strength parameters Ω₅ (t=2,4,6) for all the samples are calculated and compared. The nonradiative decay rate of the Er^{3+ 4}I_13/2 → ⁴I_15/2 transition are calculated for the glass samples with different phonon energy and OH^- group contents. Finally, the effect of OH^- groups on fluorescence decay rate of Er³⁺ is analysed, the constant K_OH-Er of TWN, TZPL and TZL glasses are calculated to be 9.2×10^-19cm⁴s^-1, 5.9×10^-19cm⁴s^-1, and 3.5×10^-19cm⁴s^-1, respectively.