On the thermal response of LuAG:Ce single crystals

It is well known that the luminescence efficiency of single crystals is affected by external parameters, such as the environmental temperature, especially in harsh environments. Due to this, it is of worth to examine the influence of temperature on the luminescence output of single-crystal scintillators. In this study lutetium aluminum garnet (Lu3Al5O12:Ce-LuAG:Ce) was examined, against previously published data for cadmium tungstate (CdWO4) and calcium fluoride doped with europium (CaF2:Eu) single crystals. Experiments were carried using a medical X-ray source, set to fixed high voltage (90kVp) and tube current/exposure time product (63mAs), in order to record the produced light, under different temperature conditions (20-120 Celsius). An interesting finding is that temperature, in the examined range, appear to have minimal influence on the light output of LuAG:Ce, in the contrary to the previously examined crystals (CdWO4 and CaF2:Eu) where the luminescence output constantly decreased with increasing temperature. The thermal stability of LuAG:Ce, in the examined temperature range, renders it a good choice, besides medical imaging, also for application in harsh environments as well as for long-term operation in high power LEDs.