We report results of a new technique to measure the electric dipole moment of ${}^{129}\mathrm{Xe}$ with ${}^3\mathrm{He}$ comagnetometry. Both species are polarized using spin-exchange optical pumping, transferred to a measurement cell, and transported into a magnetically shielded room, where SQUID magnetometers detect free precession in applied electric and magnetic fields. The result from a one week measurement campaign in 2017 and a 2.5 week campaign in 2018, combined with detailed study of systematic effects, is $d_A({}^{129}\mathrm{Xe})=(1.4\pm 6.6_{\mathrm{stat}}\pm 2.0_{\mathrm{syst}})\times {10}^{-28}e\mathrm{cm}$. This corresponds to an upper limit of $|d_A({}^{129}\mathrm{Xe})|<1.4\times {10}^{-27}e\mathrm{cm}$ (95% C.L.), a factor of 5 more sensitive than the limit set in 2001.

• Received 8 February 2019
• Corrected 16 November 2020

DOI:https://doi.org/10.1103/PhysRevLett.123.143003