Rare earth doped LiCaAlF6 as a new potential dosimetric material

Abstract

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 100mGy (with a sensitivity limit of 10−5Gy). 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.