Role of Aluminum in Ytterbium–Erbium Codoped Phosphoaluminosilicate Optical Fibers

✍ Scribed by G.G. Vienne; W.S. Brocklesby; R.S. Brown; Z.J. Chen; J.D. Minelly; J.E. Roman; D.N. Payne

• Book ID: 102616683
• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 207 KB
• Volume: 2
• Category: Article
• ISSN: 1068-5200
• DOI: 10.1006/ofte.1996.0044

✦ Synopsis

We report on a series of ytterbium᎐erbium codoped aluminophosphosilicate fibres fabricated by the modified chemical vapor deposition and solution doping technique where the concentration of aluminum is gradually increased in the region [ ] [ ] A1 -P . We observe from deflection measurements that with increasing aluminum content the refractive index decreases and the phase separation increases. Laser slope efficiencies decrease when the aluminum concentration approaches the phosphorus concentration and the trend is seen to be correlated with the reduction in energy transfer rate when the aluminum concentration is increased. Raman spectra show the reduction of the highest phonon energy peak when the aluminum content is increased. The erbium 4 I ª 4 I transition fluorescence 13r r r r r2 1 5 r r r r r 2 spectrum and the lifetime of the erbium 4 S level show little 3r r r r r2 change from the pure phosphosilicate host for the whole range of aluminum concentrations tested. The results are explained in term of formation of AlPO structural units.