Investigation of thermal stability and spectroscopic properties in Er3+ doped bismuth–boron–germanium glasses

A series of Er3+-doped 50Bi2O3-(50-x)B2O3-xGeO2+0.5 wt% Er2O3 (x=0, 5, 10, 15, 20 mol%) glasses were prepared. The thermal stability, absorption spectra, emission spectra and lifetime of the 4I13/2 level of Er3+ ions were measured and studied. It is found that the absorption cross-section of Er3+, emission intensity and lifetime of the 4I13/2 level of Er3+ increase with increasing GeO2 content in the glass composition, while the fluorescence full-width at half-maximum (FWHM) at 1.5 μm of Er3+ is about 79 nm in x=20 mol% glass sample under 970 nm pump. The obtained data suggest that this system glass can be used as a candidate host material for potential broadband optical amplifiers.