Atomic electric dipole moments of He and Yb induced by nuclear Schiff moments

TL;DR

This paper calculates atomic electric dipole moments for helium-3 and ytterbium-171 induced by nuclear Schiff moments, providing essential data for ongoing and future experiments probing fundamental symmetries in physics.

Contribution

The study provides the first detailed calculations of atomic EDMs for He and Yb induced by nuclear Schiff moments, aiding experimental efforts to detect CP violation.

Findings

d(He) = 8.3 x 10^{-5} units

d(Yb) = -1.9 x 10^{-17} e cm

Yb EDM is about 0.6 times that of Hg

Abstract

We have calculated the atomic electric dipole moments (EDMs) d of ^3He and ^{171}Yb induced by their respective nuclear Schiff moments S. Our results are d(He)= 8.3x10^{-5} and d(Yb)= -1.9 in units 10^{-17}S/(e{fm}^3)e cm. By considering the nuclear Schiff moments induced by the parity and time-reversal violating nucleon-nucleon interaction we find d(^{171}Yb)~0.6d(^{199}Hg). For ^3He the nuclear EDM coupled with the hyperfine interaction gives a larger atomic EDM than the Schiff moment. The result for ^3He is required for a neutron EDM experiment that is under development, where ^3He is used as a comagnetometer. We find that the EDM for He is orders of magnitude smaller than the neutron EDM. The result for Yb is needed for the planning and interpretation of experiments that have been proposed to measure the EDM of this atom.