Spectroscopic properties and thermal stability of Er 3+-doped TeO 2–B 2O 3–Nb 2O 5–ZnO glass for potential WDM amplifier

Abstract

A series of novel 70TeO 2–(15 − x)B 2O 3– xNb 2O 5–15ZnO–1 wt.% Er 2O 3 (TBN x = 0, 3, 6, 9, 12 and 15 mol%) tellurite glasses were prepared. The thermal stability, absorption spectra, emission spectra, and the lifetime of the 4I 13/2 level of Er 3+ ions were measured and investigated. Three Judd–Ofelt intensity parameters Ω t ( t = 2, 4 and 6) ( Ω 2 = (5.42–6.76) × 10 −20 cm 2; Ω 4 = (1.37–1.73) × 10 −20 cm 2; Ω 6 = (0.70–0.94) × 10 −20 cm 2) of Er 3+ ions were calculated by Judd–Ofelt theory. It is found that the Ω 6 first increases with the increase of Nb 2O 5 content from 0 to 6 mol% and then decreases, which is mainly affected by the number of non-bridging oxygen ions of the glass network. The high peak of stimulated emission cross-section ( σ e peak = ( 0.77 – 0.91 ) × 10 − 20 c m 2 ) of Er 3+: 4I 13/2 → 4I 15/2 transition were obtained according to McCumber theory and broad full width at half maximum (FWHM = 65–73 nm) of the 4I 13/2 → 4I 15/2 transition of Er 3+ ions were measured. The results indicate that these new TBN glasses can be used as a candidate host material for potential broadband optical amplifiers.