Temperature-dependent fluorescence characteristics of an ytterbium-sensitized erbium-doped tellurite glass

Abstract

In this article, the 1.5 μm emission spectra corresponding to the 4I 13/2→ 4I 15/2 transition of Er 3+ in tellurite glass are studied within the temperature from 8 to 300 K. The emission spectra of Er 3+: 4I 13/2→ 4I 15/2 transition are also analyzed using a peak-fit routine, and an equivalent four-level system is proposed to estimate the stark splitting for the 4I 15/2 and 4I 13/2 levels of Er 3+ in the tellurite glass. The results indicate that the 4I 13/2→ 4I 15/2 emission of Er 3+ can exhibit a considerable broadening due to a significant enhance the peak a′, and b′ change, respectively, and the peaks of which are located at about 1507 and 1556 nm. A detailed study of temperature-dependent 1.5 μm emission spectra involving the change of the corresponding sub-bands shows that as the temperature decreases from 300 to 8 K, its line-shape becomes sharper and more intense (the full-width at half-maximum decreases from 59 to 38 nm). Temperature-dependent fluorescence intensities and the experimentally determined lifetimes are investigated; the results show that a decrease behavior of fluorescence intensities and lifetimes are observed for temperature from 8 to 300 K.