Enhancing 1.8 μm emission from ultra-broadband Tm-Bi-Er tri-doped fluorotellurite glasses for fiber amplifiers and near-infrared lasers

Abstract Fluorotellurite glasses tri-doped with Tm 3+ , Er 3+ and Bi ions were investigated. The measured parameter ΔT (116 °C) confirmed that the prepared glasses had good stability. An ultra-broadband fluorescence emission (950–1670 nm) was observed with a full-width at half-maximum (FWHM) of 560 nm, which covered the entire bands of O, E, S, C, L and U. The 1800 nm fluorescence intensity of Tm 3+ /Er 3+ co-doped and Tm 3+ /Er 3+ /Bi tri-doped glasses was enhanced compared to Tm 3+ doped glass, which indicates that there is energy transfer between Tm 3+ , Er 3+ and Bi ions. The maximum fluorescence lifetime of the prepared glasses was 7.39 ms, indicating the excellent fluorescence performance at 1800 nm. Additionally, the maximum absorption cross section (σ abs = 1.77 × 10 −20 cm −2 ) and emission cross section (σ em = 7.61 × 10 −20 cm −2 ) suggest that the Tm 3+ /Er 3+ /Bi tri-doped glasses have good optical absorption properties and high gain fluorescence emission. The above results indicate that the Tm 3+ /Er 3+ /Bi tri-doped fluorotellurite glasses have good application prospects in the field of fiber amplifiers and near-infrared lasers.