Broadband 1.53 μm Emission and McCumber Analysis of Er³⁺ Doped Alkali Oxyfluorophosphate Glass for Fiber Optic Communication Material

Er³⁺ doped alkali oxyfluorophosphate glasses were prepared by the melted quenching method and characterized their optical and photoluminescence properties. Firstly, the chemical compositions of glasses were varied by changing alkali fluoride (LiF and NaF), whereas the concentration of Er³⁺ was fixed at 1.00 mol%. The optical absorption pattern and intensity were resemblance. Broadband 1.53 μm emission was one prominent peak of Er³⁺ in glass and the highest emission intensity was obtained for NaF glass under the stimulating at 521 nm. Secondly, the NaF glass was prepared by variation of Er³⁺ concentration (0.1, 0.5, 1.0, 2.0, and 4.0 mol%). The emission intensity of glasses increases with an increase in Er₂O₃ concentration up to 2.00 mol% and decreases for higher Er₂O₃ concentration, because of the concentration quenching effect. Broadband emission was observed that it covers three telecommunication windows: S, C, and L bands. The absorption and emission cross-section of 2.00 mol% of Er³⁺ doped alkali oxyfluorophosphate were found to be 1.3895 x 10⁻²⁰ cm² and 1.7248 x 10²⁰ cm⁻²_, respectively by using the McCumber theory. Both values led to the estimate of the internal gain coefficient for ⁴I_13/2→⁴I_15/2 emission transition. The gain coefficient is positive when P is higher than 40%. All results point out that Er³⁺ doped alkali oxyfluorophosphate glass could be useful for fiber optic communication material.