Spectroscopy of Dy^3+ in Ge–Ga–S glass and its suitability for 13-μm fiber-optical amplifier applications

Abstract

Absorption and emission spectra, along with lifetime measurements, of Dy³⁺ in Ge–Ga–S glasses are reported. Fluorescence is observed at 1.3, 1.8, and 2.9 μm. A Judd–Ofelt analysis is performed to determine branching ratios and quantum efficiencies. The hypersensitive transition ⁶F_11/2 → ⁶H_15/2 at 1.3 μm has a quantum efficiency of 17%. Its suitability for an optical amplifier at 1.3 μm depends on the excited-state absorption from the ⁶H_11/2 and ⁶H_13/2 states, which has not yet been measured.