RF Depolarization of Potassium in a 3He-129Xe Comagnetometer

Abstract

Noble gas comagnetometers have applications to searches for spin-gravity couplings, electric dipole moments, and nuclear spin gyroscopes, but their sensitivity is still very far from fundamental limits. The previously demonstrated 3He-129Xe comagnetometer probed by an alkali metal magnetometer has both the long coherence of a noble gas and the sensitivity of an alkali metal, allowing near-quantum limited detection of nuclear spins. However, the collisions between the polarized metal and the noble gas lead to a shift in the nuclear precession frequency. Here, we show that the application of RF radiation at the hyperfine transition in potassium can achieve greater than 99.7% depolarization of the alkali metal. We also demonstrate power broadening of the Zeeman levels, and explore the limitations of this technique.