VUV spectroscopy of wide band-gap crystals doped with rare earth ions

Spectral and kinetic properties of vacuum ultraviolet (VUV) luminescence from different fluoride crystals doped with Nd3+, Er3+ or Tm3+ are discussed. Concentration quenching of VUV luminescence, the impact mechanism of the energy transfer from the matrix to the emission centers as well as nonradiative relaxation processes in the rare earth ions have been detected and studied. The crystal properties are analyzed from the viewpoint of their possible applications as materials for fast VUV scintillators and VUV solid state lasers. Only some of Nd3+ doped crystals possess simultaneously both high light output and relatively good timing properties of VUV luminescence and such crystals can be considered as promising materials for fast VUV scintillators. On the other hand, many of Er3+ and Tm3+ doped fluoride crystals are very attractive candidates as active media for tunable VUV solid state lasers with optical pumping.