Influence of ring structures on optical absorption of trivalent ytterbium in Yb-doped silica fiber

Abstract

By using first-principle calculations, trivalent ytterbium with different ring structures were investigated in Yb-doped silica fiber. The influence of ring structure is considered to study the geometric structures, stability, and valence state of these models. The population analysis, electronic properties, energy level diagram, and optical absorption were performed in the combination of DFT and TDDFT. The interstitial Yb3+ ion in 6-membered ring is more likely to be formed, and its absorption peak is at 974.5 nm originated from the 4f13-4f13 transition. This work provides a possible site of Yb3+ ion in silica fibers, which is of great importance in further research on Yb-doped fibers.