Effect of optical basicity on broadband infrared fluorescence in erbium-doped germanate glasses

Highlights: ► Influence of optical basicity on emission spectra at 1.55 μm of Er3+ ions were investigated in alkali and alkaline earth germanate glasses. ► The bandwidth and intensity of emission spectra at 1.55 μm of Er3+ depend on the optical basicity of the host glasses irrespective of the glass systems. ► The optical basicity calculated from glass composition may work as a guiding principle to obtain broadband fiber amplifier for wavelength division multiplexing systems. - Abstract: In the case of alkali and alkaline earth germanate glasses, the effect of optical basicity on emission spectra at 1.55 μm of Er3+ ions is investigated. The results indicate that the bandwidth and intensity of emission spectra at 1.55 μm of Er3+ are controlled by the optical basicity of the host glasses. As the increase of the optical basicity, the 1.55 μm emission intensity of Er3+ ions is decreased. Based on the experimental results, the optical basicity, which is calculated from glass composition, could act as a guiding principle to obtain broadband fiber amplifier in wavelength division multiplexing systems.