Growth of GSAG:Ce scintillation crystals by the Bridgman method: influence of Ce concentration and codoping

Abstract

Single crystals of Ce-doped gadolinium scandium aluminum garnet (Gd₃Sc₂Al₃O₁₂; GSAG) with Ca²⁺, Mg²⁺ and Li⁺ co-dopants were grown by the Bridgman method. Regardless of melt composition, crystals tend to grow close to the congruent composition. Introduction of Ca²⁺ or Mg²⁺, as in other Ce-doped garnets, leads to an increase of absorption below 350 nm, which may indicate formation of Ce⁴⁺ states, while no effect is seen with Li⁺ co-doping. High Ce concentration and co-doping accelerate the scintillation rise and decay times; the codopants strongly significantly reduce the afterglow.