The divalent ion codoping effect on Ce-doped (Gd, La)2Si2O7 single crystals

Ce-doped (Gd, La)2Si2O7 scintillators have fast decay time and keep high light output even at high temperature (∼150°C). To improve the scintillation properties such as light output and decay time, Ce-doped (Gd, La)2Si2O7 scintillators codoped with the divalent ions (e.g. Mg2+, Ca2+) have been studied. In this study, we focused on the other divalent ions (Sr2+ and Ba2+), and investigated their effect on the scintillation properties and temperature dependence of light output. The absorption due to Ce4+ was not observed for Sr or Ba codoping. The light outputs were degraded by Sr2+ or Ba2+ codoping, while the decay times at room temperature were not changed for the samples codoped with divalent ions. On the other hand, the temperature dependence of light output for Ba-codoped sample was improved, and the light output value at 175°C was 36,000 photons/MeV, which was 93% of that at 25°C.