Crystal growth and characterization of Eu2+ doped Cs1-xRbxCaBr3

A series of Eu2+ doped Cs1-xRbxCaBr3 solid solutions were grown using the Bridgman-Stockbarger technique. Their photoluminescence and scintillation properties are studied. Upon optical and X-ray excitation, the Cs1-xRbxCaBr3 and Eu2+ activated samples show a band, which can be attributed to the 5d-4f transition in Eu2+. The decay time constants become shorter with increasing Rb content and lie in the range of 3–4 μs. The scintillation performance of solid solutions Cs1-xRbxCa0.95Eu0.05Br3 is improved compared with the end members (CsCa0.95Eu0.05Br3 and RbCa0.95Eu0.05Br3). The best energy resolution of 6.4% at 662 keV was determined for Cs0.2Rb0.8Ca0.95Eu0.05Br3, and the best light yield, equal to 61.2% of NaI:Tl, was demonstrated by Cs0.4Rb0.6Ca0.95Eu0.05Br3.