Broadband 2.7  µm mid-infrared emissions in Er³⁺-doped PbO-PbF₂-Bi₂O₃-Ga₂O₃ glasses

Broadband emission at 2.7 µm is observed in an Er³⁺-doped PbO-PbF₂-Bi₂O₃-Ga₂O₃ glass. The measured emission band full-width-at-half-maximum (FWHM) is ∼184.4nm, approximately 36 nm wider than that of fluoride glasses. The 2.7 µm emission intensity is almost twice as strong as that of fluoride glasses. The peak values of emission and absorption cross-sections are calculated to be 1.54×10^-20cm² and 1.19×10^-20cm², respectively. This oxyfluoride heavy metal glass shows potential as broadband mid-infrared emission gain material.