Thermal Stability and Spectroscopic Properties of New Er ³⁺ /Yb ³⁺ -Codoped Tellurite Glasses

Abstract

A series of new Er3+/Yb3+-codoped 70 TeO2–5 Li2O–(25-x)B2O3–xGeO2 (TLBG, x = 0, 5, 10, 15, 20 mol%) glasses are prepared. The thermal stability and spectroscopic properties of TLBG glasses are studied. It is found that these glasses have the better thermal stability ((Tx−Tg)>150 degrees C) compared with 75 TeO2–20 ZnO–5Na2O (TZN) glass. The fluorescence full width at half maximum (FWHM) is about 77 nm, while the emission intensity and the quantum efficiency of the 4I13/2 level of Er3+ increase with the increasing GeO2 content. The maximum quantum efficiency and stimulated emission cross-section of Er3+ calculated from the McCumber theory are 93.82% and 9.0×10−21 cm2, respectively. The products of FWHM and σepeak of Er3+ in TLBG glasses are larger than those in other reported glasses. The obtained data indicate that this kind of TLBG glasses is a promising candidate host material for Er3+-doped broadband amplifiers.