Rb、Ca和Sr原子是双光子跃迁光钟的重要研究对象，其外场效应的理论研究对双光子跃迁光钟的发展起着重要作用。斯塔克频移是双光子跃迁光钟系统频移的主要来源之一，而斯塔克频移与极化率密切相关，故本项目计算这三种双光子跃迁光钟体系的极化率，为评估其斯塔克频移奠定理论基础。利用相对论芯极化势方法和相对论芯极化势与组态相互作用的联合方法计算Rb、Ca和Sr原子的矩阵元，评估圆偏光下Rb、Ca和Sr原子双光子跃迁光钟斯塔克频移。本项目的实施将填补Rb、Ca和Sr原子双光子跃迁光钟体系超极化率理论数据的空白，为抑制圆偏光下Rb、Ca和Sr双光子跃迁光钟的斯塔克频移提供可行性方案。

Rb, Ca and Sr atoms are important candidates of two-photon optical clocks. The theoretical research of the external field effects plays a significant role in the development of two-photon optical clocks. Stark shift is one of the main sources of systematic shift for two-photon optical clocks, Stark shift is related to the polarizability. Therefore, this project will calculates the polarizability of Rb, Ca and Sr two-photon optical clocks. The matrix elements of Rb, Ca and Sr atoms are calculated by using the Dirac-Fock plus core polarization (DFCP) method and the DFCP combined configuration interaction method. The Stark shift of the Rb, Ca and Sr two-photon optical clock in circularly polarized light are evaluated. The implementation of this project will fill in the gap of theoretical data for hyperpolarizabilities of Rb, Ca and Sr two-photon optical clocks, and provide a feasible scheme for suppressing the Stark shift of Rb, Ca and Sr two-photon optical clocks.