Luminescence behavior of Er3+ in glass ceramics containing BaF2 nanocrystals

The upconversion luminescence and near infrared luminescence of the Er3+ ions in transparent oxyfluoride glass ceramics containing BaF2 nanocrystals have been investigated. The formation of BaF2 nanocrystals in the glass ceramics was confirmed by X-ray diffraction and transmission electron microscopy. Stark split peaks of the near infrared emission of the Er3+ doped glass ceramics can be observed. The upconversion luminescence intensity of Er3+ in the glass ceramics increased significantly with increasing annealing time. The transition mechanisms of the upconversion luminescence have been ascribed to a two-photon process.