Scintillation and dosimetric properties of Tb-doped CaF₂translucent ceramics synthesized by the spark plasma sintering method

CaF2 translucent ceramics with different concentrations of Tb were synthesized by the spark plasma sintering (SPS) method, and their photoluminescence, scintillation and dosimetric properties were characterized. The Tb-doped samples exhibited scintillation with several sharp peaks across the range from 365–630 nm due to 4 f-4 f transitions of Tb3+ and with a broad peak at approximately 300 nm due to self-trapped excitons. Among the sample investigated, the scintillation intensity in the 365–630 nm range was highest for the 0.5% Tb-doped sample. As a dosimetric property, the Tb-doped samples exhibited thermally-stimulated luminescence (TSL) with a glow peak at approximately 90°C, and with a TSL response in a linear relationship to the X-ray dose over the dose range from 0.001 to 1 mGy. Optically stimulated luminescence (OSL) due to the 4 f-4 f transitions of Tb3+ was detected in the Tb-doped samples, moreover and the lowest detectable limit of OSL was at most 100 mGy.