Transparent glass ceramics for 1300 nm amplifier applications

The properties of an oxyfluoride glass ceramic that possesses high transparency after ceramming are described. Approximately 25 vol % of this material is comprised of cubic, fluoride nanocrystals and the remainder is a predominantly oxide glass. When doped with Pr+3, the fluorescence lifetime at 1300 nm is longer than in a fluorozirconate glass, suggesting that a significant fraction of the rare-earth dopant is preferentially partitioned into the fluoride crystal phase. This material has the added advantage of being compatible with ambient air processing.