CLEO ® Investigation of rare earth doped BaY2F8 crystals as visible emitters.

The spectroscopic investigation of some BaY₂F₈ crystals doped with Sm³⁺ or Eu³⁺ as possible visible light emitters are presented. The interest in the fluoride crystals as host lattices is due to their low phonon energy, a few hundreds of cm-1, that can lead to a highly efficient emission. In the case of Sm³⁺ andEu³⁺ the high energy (near UV) photons populate a few excited levels that can decay to a series of lower lying multiplets, thus giving rise to many different emission bands all located in the visible region .The crystals were grown by the Czochralski method and the time resolved measurements of the fluorescence of the two crystals (Sm³⁺ or Eu³⁺ doped) are presented, in order to evaluate the emission lifetime of the various manifolds involved in the luminescence and understand the potentialities of the materials.