Emissions of 1.20 and 1.38 μm from Ho³⁺-doped lithium-barium-bismuth-lead oxide glass for optical amplifications

Efficient infrared emissions at 1.20 μm [⁵I₆ → ⁵I₈ transition] and 1.38 μm [(⁵ F₄, ⁵ S₂) → ⁵I₅ transition] from Ho³⁺-doped lithium-barium-bismuth-lead (LBBP) glass were observed. The stimulated emission cross-sections were calculated to be 0.29 × 10^-20 and 0.25 × 10^-20 cm² for 1.20 and 1.38 μm emissions, respectively. Judd-Ofelt characteristic parameters Ω₂, Ω₄ and Ω₆ for Ho³⁺ in LBBP glass were calculated to be 6.72 × 10 ^-20, 2.35 × 10^-20 and 0.61 × 10^-20 cm², respectively, which indicates a strong asymmetry and a covalent environment between the Ho³⁺ ions and the ligands in this glass. The optical amplifications operating at these relatively unexplored wavelength regions were evaluated and discussed.