Evaluation of photoluminescence and dosimetric properties of undoped and Tb-doped Ba3La(PO4)3 single crystals

Abstract

To evaluate the photoluminescence (PL) and dosimetric properties, we synthesized Ba₃La(PO₄)₃ (BLPO) single crystals doped with 0, 0.1, 0.5, 1, 5, and 10 % Tb using a floating zone furnace. Tb-doped BLPO single crystals showed the PL emission peaks originating from 4f–4f transitions of Tb³⁺ ions. The PL quantum yield of the 10 % Tb-doped BLPO single crystal was about 29.4 %, the highest value in the prepared samples. In the thermally stimulated luminescence (TSL) spectra, the undoped BLPO single crystal showed a broad peak at 400 nm. The 0.1 % Tb-doped BLPO single crystal showed both broad and sharp peaks at 380–620 nm. The other Tb-doped BLPO single crystals showed only sharp peaks at 380–620 nm. The broad TSL peak at 400 nm and the sharp TSL peaks at 380–620 nm were due to self-trapped exciton and 4f–4f transitions of Tb³⁺ ions, respectively. The TSL glow curve showed glow peaks at 65 °C for the undoped BLPO single crystal and 85 °C for the BLPO single crystals doped with Tb. In the TSL dose response functions, the BLPO single crystal doped with 5 % Tb displayed a detection limit of 0.01 mGy. In the spatial resolution tests, the BLPO single crystal doped with 5 % Tb demonstrated a spatial resolution of 50.0 μm after 1 Gy of X-ray irradiation.