Measurement of the Electric Dipole Moment of $^{171}$Yb Atoms in an Optical Dipole Trap

TL;DR

This paper reports a precise measurement of the electric dipole moment of $^{171}$Yb atoms using an optical dipole trap, achieving a new upper limit and demonstrating techniques applicable to other atoms like $^{225}$Ra.

Contribution

The study introduces a novel quantum non-demolition measurement method with high spin-detection efficiency for $^{171}$Yb atoms in an optical dipole trap.

Findings

Measured the EDM of $^{171}$Yb with an upper limit of $1.5 imes 10^{-26}\, e\,cm.

Achieved a spin precession time longer than 300 seconds.

Developed techniques adaptable for EDM searches in other atoms like $^{225}$Ra.

Abstract

The permanent electric dipole moment (EDM) of the $^{171}$Yb $(I=1/2)$ atom is measured with atoms held in an optical dipole trap (ODT). By enabling a cycling transition that is simultaneously spin-selective and spin-preserving, a quantum non-demolition measurement with a spin-detection efficiency of 50$\%$ is realized. A systematic effect due to parity mixing induced by a static E field is observed, and is suppressed by averaging between measurements with ODTs in opposite directions. The coherent spin precession time is found to be much longer than 300 s. The EDM is determined to be $d({\rm^{171}Yb})={\color{black}(-6.8\pm5.1_{\rm stat}\pm1.2_{\rm syst})\times10^{-27}\ e\ \rm cm}$, leading to an upper limit of $|d({\rm^{171}Yb})|<{\color{black}1.5\times10^{-26}\ e\ \rm cm}$ ($95\%$ C.L.). These measurement techniques can be adapted to search for the EDM of $^{225}$Ra.