High-fidelity low-loss state detection of alkali-metal atoms in optical tweezer traps

Abstract

We demonstrate the discrimination of ground-state hyperfine manifolds of a cesium atom in an optical tweezer using a simple probe beam with $99.{91}_{\ensuremath{-}0.02}^{+0.02}$% detection fidelity and 0.9(2)% detection-driven loss of bright-state atoms. Our detection infidelity of $0.{09}_{\ensuremath{-}0.02}^{+0.02}$% is an order of magnitude better than previously published low-loss readout results for alkali-metal atoms in optical tweezers. We achieve these results by identifying and mitigating an extra depumping mechanism due to stimulated Raman transitions induced by trap light in the presence of probe light. In this work, complex optical systems and stringent vacuum pressures are not required, enabling straightforward adoption of our techniques on contemporary experiments.