Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1990 · 24 citations · 0 references
Natural SciencesMaterials SciencePhysicsOptical MaterialsOpticsSpectroscopyFiber OpticsGlass MaterialsOptical FibersOptical GlassesOptical Properties Of MaterialsRare-earth-doped MaterialsDecay TimeRare Earth-doped GlassesRare-earth-doped FibersRare-earth-doped GlassesSilica Fiber MaterialsSilicate GlassesSingle-mode FibersSingle-mode Optical Fibers
Optical absorption strengths and spontaneous transition rates are presented for Er3+ ions in Ge-doped silica glass at concentrations from 0.5x1019 cm-3 to 4.0x1019 cm-3. Results for transitions in the 480 - 1700-nm range are extracted from measure-ments on Er-doped preform cores prepared by the solution-doping technique. A com-parison of the spontaneous lifetime of the 4113/2 level with the strength of the corresponding ground-state absorption reveals a conflict with the Einstein A-B relation. Measurements made on fibers exhibit a significant change in linewidth and fluorescence decay time as compared to the corresponding preforms. From these results the magnitude and spectral dependence of the cross sections for absorption as well as stimulated emission were determined for single-mode fibers.