Nanocomposite, Ceramic, and Thin Film Scintillators

In this presentation related to the nanocomposite, ceramic and thin film scintillators the recent results achieved at ZnO, aluminum garnet and silicate material systems will be presented. In case of ZnO, technological ways to prepare it in powder form doped by Ga or other trivalent donor ions are searched to maximize the exciton superfast (below 1 ns) luminescence response and overall scintillation efficiency. In the case of aluminum garnets RE3Al5O12 (RE=Y, Lu), abbrev. as YAG, LuAG, the Ce3+ and Pr3+ dopants are mainly used to achieve the scintillation response in the range of tens of ns. Liquid phase epitaxy is employed to manufacture single crystalline thin films (1-20 us) grown on YAG or LuAG substrate with the help of PbO-, BaO or Mo2O3-based fluxes. Flux-based contamination, growth defects and morphology of the transition layer and their influence on scintillation performance is of interest. Optical ceramics prepared by high temperature sintering or low temperature very high presure techniques are compared with bulk single crystal analogues as for their defectness and scintillation parameters achieved. Finally, composite scintillators based on the SiO2-RE2Si2O7:Ce system are under study using sol-gel techniques. The silicate nanophase dispersed in SiO2 glass matrix shows interesting luminescence and scintillation characteristics. Practical potential of all the studied materials will be discussed.