A paradigmatic model in quantum metrology is the one-axis twisting Hamiltonian, comprising all-to-all Ising interactions that dynamically generate resources for entanglement-enhanced spectroscopy, notably squeezed and Schrödinger cat states. Generalizing this approach to systems with local interactions significantly expands the range of platforms amenable to quantum-enhanced sensing. I will report on past and ongoing experiments leveraging Rydberg interactions to realize locally interacting variants of one-axis twisting. To generate squeezed states in an array of atomic ensembles, we applied off-resonant Rydberg dressing to controllably induce Ising interactions among spins encoded in long-lived ground states. In current work aimed at generating Schrödinger-cat-like states in an array of single atoms, we instead leverage dipolar spin exchange between Rydberg states to enable spreading of correlations and to protect the collective spin coherence. A “twist-again” decoding protocol enables robust detection of the spectroscopic signal. I will also touch on broader prospects for scalably entangling dipolar Rydberg atoms, from squeezing towards the Heisenberg limit by gap-protected two-axis twisting to augmenting the interaction range by strong coupling to a millimeter-wave cavity.
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