Investigation of spectroscopic properties and thermal stability of Er 3+/Yb 3+-co-doped Bi 2O 3–B 2O 3–Ga 2O 3 glasses

Abstract

A series of Er 3+/Yb 3+-co-doped 60Bi 2O 3–(40− x) B 2O 3 – xGa 2O 3 (BBGA x=0, 4, 8, 12, 16 mol%) glasses have been prepared. The absorption spectra, emission spectra, fluorescence lifetime of Er 3+: 4I 13/2 level and thermal stability were measured and investigated. Three Judd–Ofelt intensity parameters Ω t ( t=2,4,6) ( Ω 2=(4.67–5.93)×10 −20 cm 2, Ω 4=(1.50–1.81)×10 −20 cm 2, Ω 6=(0.92–1.17)×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 Ga 2O 3 content from 0 to 8 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 = 0.83 - 1.03 × 1 0 - 20 cm 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=69–76 nm) of the 4I 13/2→ 4I 15/2 transition of Er 3+ ions were measured. The results indicate that these new BBGA glasses can be used as a candidate host material for potential broadband optical amplifiers.