2024/09/13 by Timo Fleig, Fleig, Timo
Physics and Astronomy · #Atomic Physics (physics.atom-ph) #Atomic and Molecular Physics #Atomic physics #FOS: Physical sciences #Hyperfine structure #Nuclear physics research studies #Physics #Quantum Physics (quant-ph) #Radioactive Decay and Measurement Techniques
paper · pdf · doi:10.48550/arxiv.2409.08787
openalex publication_date 2024/09/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
An electronically variational approach to the calculation of atomic hyperfine structure transition energies under the influence of static external electric fields is presented. The method avoids the calculation of intermediate atomic states entirely and requires only the wavefunctions of the electronic states involved in the respective hyperfine levels. These wavefunctions are obtained through relativistic general-excitation-rank configuration interaction theory. A variant of the method also enables for calculations on atoms with the most complicated of shell structures. Applications to 87Rb, 133Cs and a specific clock transition in 169Tm are presented. The final results kRb = -1.234 ± 0.0223 [10-10 Hz/((V/m)2)] and kCs = -2.347 ± 0.084 [10-10 Hz/((V/m)2)] obtained under inclusion of up to quintuple excitations in the atomic wavefunction expansion are compatible with previous calculations and, in the case of Cs, confirm that one of the earlier experimental measurements is not reliable. For 169Tm that is used in the development of atomic clocks the differential static scalar electric dipole polarizability between ground levels J=(7)/(2) and J=(5)/(2) is calculated to be Δαs0 = -0.134 ± 0.11 a.u. This result from a pure \itab initio calculation confirms the result of Δαs0 = -0.063+0.01-0.005 a.u. obtained in \itNat. Comm. \bf10 (2019) 1724 where a combination of measurement and theoretical modeling has been used.