物理学报2019，Vol.68Issue(4)：208-213,6.DOI:10.7498/aps.68.20182136
Hg+离子5d106s 2S1/2→5d96s2 2D5/2钟跃迁同位素位移和超精细结构的理论研究
Theoretical investigation on hyperfine structure and isotope shift for 5d106s 2S1/2→5d96s2 2D5/2 clock transition in Hg+
摘要
Abstract
The Dirac-Hartree-Fock approximation is adopted to calculate the mass shift and the field shift for the 5d106s 2S1/2→5d96s2 2D5/2 clock transition in Hg+. It is found that the field shift is much larger than the mass shift so that the latter can be neglected in the isotope shift. In addition, we estimate that the isotope shifts of the levels related to the 5d106s 2S1/2→5d96s2 2D5/2 clock transition of Hg+ is on the order of about 104 GHz, while the hyperfine structure splitting is in a range of 1?10 GHz. However, the isotope shift of the 5d106s 2S1/2→5d96s2 2D5/2 clock transition is on the same order of magnitude as the hyperfine structure splitting. Therefore, the hyperfine structure splitting must be taken into account for predicting the frequency shifts of the clock transition between different isotopes. On the basis of these results, we perform a multi-configuration Dirac-Hartree-Fock calculation on the field shift of the 5d106s 2S1/2→5d96s2 2D5/2 clock transition in Hg+ and the hyperfine interaction constants of the upper and the lower levels involved. In order to give accurate theoretical results of these physical quantities, we systematically consider the main electron correlations in the atomic system by using the active space method. The restricted single and double (SrD) excitation method is used to capture the correlation between the 5d and the 6s valence electrons, and the correlation between the 3s, 3p, 3d, 4s, 4p, 4d, 5s, 5p, and 5d core and the valence electrons. The isotope shifts and hyperfine structure splitting for this transition of several stable mercury isotopes are given. In particular, the uncertainty of the calculated isotope shift between 199Hg+ and 198Hg+ is about 2％, compared with the experimental measurement available. Using these results, we predict the absolute frequency values of this transition for seven mercury isotopes, which provides theoretical reference data for experiments. Moreover, the calculated isotope shifts and hyperfine structures are also useful for studying the structure, property and nucleon interaction of mercury nucleus.关键词
超精细结构/同位素位移/多组态Dirac-Hartree-Fock方法/汞离子光钟Key words
hyperfine structure/isotope shift/multi-configuration Dirac-Hartree-Fock method/mercury ion clock引用本文复制引用
张祥,卢本全,李冀光,邹宏新..Hg+离子5d106s 2S1/2→5d96s2 2D5/2钟跃迁同位素位移和超精细结构的理论研究[J].物理学报,2019,68(4):208-213,6.基金项目
国家自然科学基金(批准号: 11604385, 91536106, 11204374, 11874090) 和国防科技大学研究项目(批准号: ZK17-03-11) 资助的课题. （批准号: 11604385, 91536106, 11204374, 11874090）
