Spectroscopic properties of Er3+/Yb3+ co-doped Bi2O3B2O3GeO2 glasses

Er3+/Yb3+ co-doped 60Bi2O3(40 − x)B2O3xGeO2 (BBG; x = 0, 5, 10, 15 mol%) glasses that are suitable for fiber lasers, amplifiers have been fabricated and characterized. The absorption spectra, emission spectra, and lifetime of the 4I13/2 level and quantum efficiency of Er3+:4I13/2 → 4I15/2 transition were measured and calculated. With the substitution of GeO2 for B2O3, both Δλeff and σe decrease from 75 to 71 nm and 9.88 to 8.12 × 10−21 cm2, respectively. The measured lifetime of the 4I13/2 level and quantum efficiency of Er3+:4I13/2 → 4I15/2 transition increase from 1.18 to 1.5 ms and 36.2% to 43.2%, respectively. The emission spectra of Er3+:4I13/2 → 4I15/2 transition was also analyzed using a peak-fit routine, and an equivalent four-level system was proposed to estimate the stark splitting for the 4I15/2 and 4I13/2 levels of Er3+ in the BBG glasses. The results indicate that the 4I13/2 → 4I15/2 emission of Er3+ can be exhibit a considerable broadening due to a significant enhance the peak A, and D emission.