Earth fluorescence in novel oxyfluoride glasses and glass-ceramics

Transparent oxyfluoride glass-ceramics can provide a low-phonon energy fluoride environment for active rare earth ions while maintaining the durability, formability, and mechanical strength of an oxide glass. Fluorescence from RE doped samples indicate substantial partitioning into the fluoride crystals. Eu3+ doped glasses emit only red luminescence from the D-5(0), but after heat treatment emit blue, green, and red luminescence, indicative of a low phonon energy rare earth environment. Er3+ doped samples show broadening and flattening of the 1530 emission band upon heat treatment, making them attractive for broad band amplifiers. Cerammed Pr3+ doped samples exhibit 240 mu s (1)G(4) fluorescent lifetimes, which indicates a 1310 nm quantum efficiency of 8%. Tt was determined that active rare earth partitioning into the LaF3 nanocrystallites that form upon heat treatment are responsible for the novel optical properties of these hybrid materials.