True mid-infrared Pr3+ absorption cross-section in a selenide-chalcogenide host-glass

The mid-infrared (MIR) spans the 3 – 25 µm wavelength range. Rare-earth-ion doped selenide-chalcogenide glasses are being developed for direct-emission MIR fibre lasers. The true Pr
³⁺
absorption cross-section in the 3.5 – 6 µm wavelength region of a Pr
³⁺
-doped (500 ppmw of Pr
³⁺
i.e. 9.47×1019 Pr
³⁺
ions cm
⁻³
) GeAsGaSe host-glass is presented, after numerically removing the underlying, extrinsic vibrational absorption due to [H-Se-] contamination of the host-glass.