Feasibility and potential of a thorium-doped barium-lithium-fluoride single crystal as a candidate for solid-state nuclear optical clock material

In recent twenty years, the research on nuclear clocks based on Th nuclear transition has become increasingly intensive. Among them, solid-state nuclear clocks based on thorium -doped crystals are considered to have unique advantages in the detections of accurate energy and lifetime of nuclear isomers and the stability and miniaturization of optical clocks. In this work, The feasibility and potential of using Th:BaLiF3 single crystal as a solid-state nuclear clock material was calculated and predicted by using density functional theory (DFT). The theoretical results showed that Th ions could be effectively doped in BaLiF3 crystal through a suitable charge compensation mechanism, and only slightly decreased the transmittance of BaLiF3 crystal in the nuclear transition band. On this basis, a Th:BaLiF3 single crystal was successfully grown through experiments. Th concentration of the as -grown crystal can reach 3.13 x 1018 cm-3, and the transmittance can reach T similar to 50% at similar to 150 nm. Compared with the pure BaLiF3 crystal grown under similar conditions, it only slightly decreased. The Th:BaLiF3 single crystal is expected to be a potential candidate for solid-state nuclear clock material.