Intense ultraviolet emission from Tb3+ and Yb3+ codoped glass ceramic containing CaF2 nanocrystals

Abstract

A transparent Tb 3 + and Yb 3 + codoped oxyfluoride glassceramic containing Ca F 2 nanocrystals was developed. This glassceramic showed an intense ultraviolet emission at 381 nm due to the G 6 5 , D 3 5 → F 6 7 transitions of Tb 3 + ion when excited with a 974 nm laser at room temperature. The observed intense ultraviolet emission could be attributed to the change of ligand field of Tb 3 + and Yb 3 + ions due to the incorporation of some Tb 3 + and Yb 3 + ions into Ca F 2 nanocrystals, and the resulting increased branching ratio of the transitions and longer lifetime of D 4 5 level of Tb 3 + in the glassceramic.