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arXiv · 2109.06623

Using optical clock transitions in Cu II and Yb III for time-keeping and search for new physics

Abstract

We study the $^1$S$_0 - ^3$D$_2$ and $^1$S$_0 - ^3$D$_3$ transitions in Cu II and the $^1$S$_0 - ^3$P$^{\rm o}_2$ transition in Yb III as possible candidates for the optical clock transitions. A recently developed version of the configuration (CI) method, designed for a large number of electrons above closed-shell core, is used to carry out the calculation. We calculate excitation energies, transition rates, lifetimes, scalar static polarizabilities of the ground and clock states, and blackbody radiation shift. We demonstrate that the considered transitions have all features of the clock transition leading to prospects of highly accurate measurements. Search for new physics, such as time variation of the fine structure constant, is also investigated.

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Saleh O. Allehabi, V. A. Dzuba, V. V. Flambaum. 2021-09-14. Using optical clock transitions in Cu II and Yb III for time-keeping and search for new physics. https://doi.org/10.1103/physreva.104.053109

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