X-ray-induced scintillation properties of Nd-doped calcium niobium gallium garnet single crystals

0.1, 0.5, and 1 % Nd-doped Ca3Nb1.6875Ga3.1875O12 (CNGG) single crystals were successfully synthesized by the Floating Zone method. The optical and scintillation characteristics in ultraviolet–near-infrared (NIR) regions were investigated. All the CNGG crystals showed emissions at 900, 1060, and 1350 nm, which correspond to the typical electronic transitions of Nd3+. The decay times of 200–220 μs were obtained by an approximation of decay curves. The values were valid as the 4f–4f transitions of Nd3+. When relationships between X-ray irradiation dose-rate and output signals in NIR ranges were evaluated, all the prepared samples exhibited good linear responses. The lowest detectable dose-rate in prepared samples was observed by measuring with the 0.5 % Nd-doped sample, and the value was 0.006 Gy/h.