The recently-developed technique of atom-by-atom assembly has allowed for the generation of large atomic qubit registers with zero defect entropy. When the atoms in such a system are excited to Rydberg states, they experience long-range interactions that enable many-body interatomic entanglement of their internal states. Until recently, such techniques had been realized only in single-electron atoms, though two-electron atoms promised several benefits and new possibilities. In this talk, we discuss the realization of a number of these benefits in a new experiment implementing atom-assembly and Rydberg entanglement in an array of two-electron strontium atoms. We begin by showing the first trapping, cooling to near the motional ground state, high-fidelity imaging, and array assembly of single strontium atoms. By exploiting several features of the two-electron level structure, we generate entangled Bell pairs on the Rydberg transition at leading fidelities. We furthermore demonstrate an improvement in Rydberg state-readout infidelity by over an order of magnitude compared to previous work. We readily extend these techniques to larger system sizes, and show preliminary quantum simulation of an Ising spin chain and light-cone correlation spreading in a many-body system. We conclude with outlooks on a spin-squeezed optical clock that combines the ultra-narrow clock transition of strontium with Rydberg interactions for a new regime of entanglement-enhanced metrology.
Via Zoom: https://princeton.zoom.us/j/99580784825