Dosimetric properties of Tb-doped LiF/CaF2 eutectic composite

Abstract

We have developed a LiF/CaF2:Tb eutectic composite as a novel thermoluminescence (TL) dosimetric material. The LiF/CaF2:Tb eutectic composite was obtained using a melt-solidification method with a lower melting temperature than that of LiF and CaF2. The results of the PL emission and excitation spectra, the X-ray induced radioluminescence decay curve, and the TL emission spectrum indicate that the emissions of LiF/CaF2:Tb eutectic composite are due to 4f-4f transitions of the Tb3+ ion. The integrated TL intensity of the LiF/CaF2:Tb eutectic composite was 3.6 times higher than that of the commercial CaSO4:Tm dosimetric material that is known to show a relatively high TL intensity. The dose response curve of the LiF/CaF2:Tb eutectic composite was measured and the lower detection limit was 0.01 mGy which is the lowest value among the LiF/CaF2 based composites.