Seminar: Jacob Hines, Stanford University

Spin squeezing by Rydberg dressing in an array of atomic ensembles

Ensembles of neutral atoms enable state-of-the-art measurements of time, acceleration, and electromagnetic fields. Introducing entanglement in the form of spin squeezing among the constituent atoms offers a route to enhancing the precision of these measurements. In this talk, I will report on the creation of an array of spin-squeezed ensembles of cesium atoms via Rydberg dressing, a technique that offers optical control over local interactions between neutral atoms. We optimize the coherence of the interactions by a stroboscopic dressing sequence that suppresses super-Poissonian loss. We thereby prepare squeezed states of N = 200 atoms with a metrological squeezing parameter 0.77(9) quantifying the reduction in phase variance below the standard quantum limit. We realize metrological gain across three spatially separated ensembles in parallel, with the strength of squeezing controlled by the local intensity of the dressing light. Our method can be applied to enhance the precision of tests of fundamental physics based on arrays of atomic clocks and to enable quantum-enhanced imaging of electromagnetic fields.