Rare earth doped LiCaAlF₆ as a new potential dosimetric material

LiCaAlF₆ (LiCAF) crystals doped with two different rare earth (RE) ions (europium and cerium) have been investigated as potential new dosimetric materials. Thermally stimulated luminescence (TSL) measurements have been carried out and a quantitative comparison has been performed with a standard LiF dosimetric material. Wavelength-resolved TSL measurements have revealed that the TSL spectrum is dominated by RE-related emissions with no significant contributions from defect centers. The glow curve of LiCAF:Eu displays a dosimetric peak at about 240 °C with a good linearity versus imparted dose. Specifically, the material appears more sensitive than LiF at doses lower than 100 mGy (with a sensitivity limit of 10^-5 Gy). Concerning LiCAF:Ce, the glow curve is more complicated, dose memory effects appear and no peaks with good dosimetric properties are found. Therefore, LiCAF:Eu seems to be more promising in the search for a new dosimetric material.