Fabrication and characterization of bismuth-doped germano-silicate and phospho-silicate fibers for VIS/NIR applications

We report a reproducible fabrication process ensuring repeatable absorption and emission properties of bismuth (Bi) doped silica-glass optical fibers (BDFs) with single-mode operation above ∼800 nm. BDFs were fabricated through a modified chemical vapor deposition process in-line with the solution-doping technique. Lithium-germanosilicate, yttrium-germanosilicate, and yttrium-phosphosilicate glasses were used as hosts for Bi. Bi and other dopant concentrations were measured by EPMA. ∼0.07wt% of Bi content is obtained with a transparent core. The absorptive and emissive properties of BDFs in the VIS-NIR range (targeted onto 600-900 nm) were studied thoroughly. This study is oriented to the development of VIS/NIR lasers and amplifiers, using BDFs of this type.