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arXiv · 2311.10409

Relativistic hyperpolarizabilities for atomic H, Li, and Be$^+$ systems

Shan-Shan Lu·Hong-Yuan Zheng·Zong-Chao Yan·James F. Babb·Li-Yan Tang
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Abstract

The hyperpolarizability of an atom is a property that describes the nonlinear interaction between an atom and an external electric field leading to a higher-order Stark shift. Accurate evaluations of these coefficients for various systems are crucial to improve experimental precision in advanced atom-based clocks. However, there is a dearth of reports on atomic hyperpolarizabilities, particularly regarding relativistic hyperpolarizabilities. Thus, in this paper, we use fourth-order perturbation theory to establish a universal formula for the hyperpolarizability and calculate the relativistic hyperpolarizabilities of low-lying states for the monovalent electronic atomic systems H, Li, and Be$^+$. The highly accurate results given here for the H atom could serve as benchmarks for other theoretical methods.

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Shan-Shan Lu, Hong-Yuan Zheng, Zong-Chao Yan, James F. Babb, Li-Yan Tang. 2023-11-17. Relativistic hyperpolarizabilities for atomic H, Li, and Be$^+$ systems. https://doi.org/10.1088/1674-1056/ad9911

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