Search for an axion-induced oscillating electric dipole moment for electrons using atomic magnetometers

We propose an experimental search for an axion-induced oscillating electric dipole moment (OEDM) for electrons using state-of-the-art atomic magnetometers. The axion is a hypothesized new fundamental particle which can resolve the strong charge-parity problem and be a prominent dark matter candidate. This experiment utilizes optically polarized electron spins in an alkali-metal vapor cell of atomic magnetometers. The interaction of the axion field, oscillating at a frequency equal to the axion mass, with a magnetic dipole moment induces a sizable OEDM of electrons at the same frequency as the axion field. The OEDM interacts with an electric field, which results in an effective oscillating magnetic signal when the atomic vapor cell is subjected to a strong electric field. The resulting magnetic signal can be sensitively detected with a probe beam of the atomic magnetometer. We estimate that the experiment is sensitive to the axion-photon interaction in ultra-light axion mass ranges from 1e-15 to 1e-10 eV and push down the current experimental limit up to 5 orders of magnitude, exploring new axion parameter spaces.