Atomic Clock States of Thulium have Near-Zero Electric Quadrupole Moment

Timo Fleig

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arXiv · 2302.01840

Atomic Clock States of Thulium have Near-Zero Electric Quadrupole Moment

Timo Fleig

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Abstract

A method for highly accurate calculations of atomic electric quadrupole moments (EQM) is presented, using relativistic general-excitation-rank configuration interaction wavefunctions based on Dirac spinors. Application to the clock transition states of the thulium atom employing up to full Quadruple excitations for the atomic wavefunction yields a final value of $Q_{zz}({^2F}_{7/2}) = 0.07 \pm 0.07$ a.u., establishing that the thulium electronic ground state has an exceptionally small EQM. A detailed analysis of this result is presented which has implications for EQMs of other atoms with unpaired $f$ electrons.

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Timo Fleig. 2023-02-03. Atomic Clock States of Thulium have Near-Zero Electric Quadrupole Moment. https://arxiv.org/abs/2302.01840

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