Visible emission of Tb3+-Yb3+ co-doped fluorophosphate glasses

Visible lasers and amplifiers have potential applications in the fields of optical data storage, spectroscopy, biomedical and optical local area networks. In this study, Tb3+-Yb3+, co-doped fluorophosphate glasses were synthesized and properties of the visible emission at 0.54,mu m were investigated. A upconversion excitation efficiency from Yb3+ to Tb3+ was studied by evaluations of a cooperative energy transfer efficiency from Yb3+, to Tb3+ (eta(CET)) and a back-transfer efficiency from Tb3+ to Yb3+ (eta(BT)) which give positive and negative contribution to upconversion excitation, respectively. The eta(CET) was as high as 25 %, and the eta(BT) was less than 1% in the fluorophosphate glass. This indicates that Tb3+ -Yb (3+) co-doped fluorophosphate glass is promising as new laser and gain media in the 0.54 mu m band.