Spectroscopic properties of Er³⁺, Yb³⁺, Tm³⁺-codoped tellurite glass

Abstract

Comparative study of spectroscopic properties of Er³⁺/Tm³⁺-codoped and Er³⁺/Tm³⁺/Yb³⁺ codoped tellurite glasses under a single wavelength pumping at 980nm were investigated. In the Er³⁺/Tm³⁺-codoped tellurite glasses, we have found that there exists fluorescence emissions at both 1.53 and 1.74 μm, which correspond to the transitions of the Er³⁺:⁴I_13/2→⁴I_15/2 and Tm³⁺:³F₄→³H₆, respectively. Tm³⁺ act as an efficient co-dopant for depopulation of the Er³⁺:⁴I_13/2 level, and thus reducing the optical amplification efficiency. Meanwhile, the addition of a small amount of Tm³⁺ to the Er³⁺ doped tellurite glass causes the quenching of the green up-conversion fluorescence around 524 and 546nm resulting in red visual. In the Er³⁺/Tm³⁺/Yb³⁺ codoped tellurite glasses, fluorescence emissions at both 1.53 and 1.63 μm communication windows were firstly observed. What' more, The FWHM (fluorescence width at half maximum) at 1.53 and 1.63 μm are 55nm and 50nm, respectively. This novel three earth ions co-doping method could be applied to other low photon energy glasses, which would be possibly used for potential dual wavelength fiber-optic amplifiers to broaden the communication windows.