Enhanced 1.53-μm and lowered upconversion luminescence in Er3+-doped Ga2O3-GeO2-Bi2O3-Na2O glass by codoping rare earths

Spectroscopic properties and energy transfer (ET) in Ga2O3-GeO2-Bi2O3-Na2O (GGBN, glass doped with Er3+ and rare earths (RE3+; RE3+=Ce3+, Tb3+) have been investigated. Intense 1.53-μm emission with the peak emission cross-section achieved to 7.58×10−21 cm2 from Er3+-doped GGBN glass has been obtained upon excitation at 980 nm. Effects of RE3+ (RE3+=Ce3+, Tb3+) codoping on the optical properties of Er3+-doped GGBN glass have been investigated and the possible ET mechanisms involved have also been discussed. Significant enhancement of the 1.53 μm emission intensity and decrease of upconversion (UC) fluorescence with increasing Ce3+ concentration have been observed. The incorporation of Tb3+ into Er3+-doped GGBN glass could significantly decrease the UC emission intensity, but meanwhile decrease the 1.53 μm emission intensity due to the ET from Er3+:4I13/2 to Tb3+:7F2. The results indicate that the incorporation of Ce3+ into Er3+-doped GGBN glass can effectively improve 1.53-μm and lower UC luminescence, which makes GGBN glass more attractive for use in C-band optical fiber amplifiers.