Erasure conversion in a high-fidelity Rydberg quantum simulator

Minimizing and understanding errors is critical for quantum science, both in noisy intermediate scale quantum (NISQ) devices(1) and for the quest towards fault-tolerant quantum computation(2,3). Rydberg arrays have emerged as a prominent platform in this context(4) with impressive system sizes(5,6) and proposals suggesting how error-correction thresholds could be significantly improved by detecting leakage errors with single-atom resolution(7,8), a form of erasure error conversion(9–12). However, two-qubit entanglement fidelities in Rydberg atom arrays(13,14) have lagged behind competitors(15,16) and this type of erasure conversion is yet to be realized for matter-based qubits in general. Here we demonstrate both erasure conversion and high-fidelity Bell state generation using a Rydberg quantum simulator(5,6,17,18). When excising data with erasure errors observed via fast imaging of alkaline-earth atoms(19–22), we achieve a Bell state fidelity of [Formula: see text] , which improves to [Formula: see text] when correcting for remaining state-preparation errors. We further apply erasure conversion in a quantum simulation experiment for quasi-adiabatic preparation of long-range order across a quantum phase transition, and reveal the otherwise hidden impact of these errors on the simulation outcome. Our work demonstrates the capability for Rydberg-based entanglement to reach fidelities in the 0.999 regime, with higher fidelities a question of technical improvements, and shows how erasure conversion can be utilized in NISQ devices. These techniques could be translated directly to quantum-error-correction codes with the addition of long-lived qubits(7,22–24).