Preliminary studies towards implementing quantum nondemolition spin detection in radium electric dipole moment measurements

The electric dipole moment (EDM) is an intrinsic property of atomic systems that, if it exists, directly violates time reversal symmetry (T). T violation implies charge-parity symmetry (CP) violation and the discovery of additional CP violation is necessary to explain the matter-antimatter asymmetry in the universe. A recent EDM measurement in Yb-171 demonstrated a novel spin-state detection technique that utilizes multiple laser wavelengths to inhibit decoherence via state dressing and achieved spin-state detection efficiency of 50%[T. A. Zheng et al., Phys Rev Lett. 129, 083001 (2022)]. We will report on the benefit and feasibility of adapting this technique to radium atoms. Radium, because of its highly deformed “pear-shaped” nucleus, has enhanced sensitivity to new physics compared to nearly spherical nuclei such as Yb-171 and Hg-199. This work is supported the U.S. DOE, Office of Science, Office of Nuclear Physics, under contracts DE-AC02-06CH11357 and DE-SC0019455 and is based upon work supported by the Department of Energy National Nuclear Security Administration through the Nuclear Science and Security Consortium under Award Number DE-NA0003996.