Broadband near-infrared emission covering S+C+L in Er³⁺-doped nanocrystal modified PbO-PbF₂-Bi₂O₃-Ga₂O_{3 glasses}

This paper reports a broadband near-infrared emission ranging from 1400 to 1660 nm in Er3+-doped nanocrystal-modified PbO-PbF2-Bi2O3-Ga2O3 glasses. After heat treatment, X-ray diffraction measurements were performed and confirmed that PbBiO2F nanocrystals were precipitated in the precursor glasses. As nanocrystals alter the local environment around Er3+ ions, the emission spectrum of the transition I-4(13/2)-> I-4(15/2) is broadened and enhanced, resulting in a broadband emission and an FWHM wavelength range of 143.4 nm from 1470.1 to 1613.5 nm, which overlaps the S+C+L optical communications windows. In addition, the emission intensity of the I-4(11/2)-> I-4(13/2) transition is also found to be increased after heat treatment, thus enhancing the lambda similar to 2750 nm emission intensity. Our results indicate that an Er3+-doped nanocrystal-modified PbO-PbF2-Bi2O3-Ga2O3 glass could be a competitive candidate material that can offer improved bandwidths for S+C+L broadband amplifiers used in very high-capacity optical communications systems