Improving the fidelity of entangling gates for quantum simulations and computation with neutral atoms

Errors in quantum operations represent the key limitation of quantum information processors.  For neutral atom quantum processors, the error due to the two-qubit gate is a dominant noise source, limiting both the accessible circuit depths for algorithms with physical qubits [1] and below-threshold performance in fault-tolerant architectures that use logical encoding and quantum error correction [2].  Here, we demonstrate two-qubit entangling CZ operations with raw fidelities of 99.84% and atom loss post-selected fidelities of 99.95%. These low error rates are achieved through a combination of higher laser intensities resulting in fast gates, improved calibration techniques, including fast calibrations at ~30Hz cycle rates with spin-selective readout, as well as improved beam intensity and pointing stabilization. These advances enable new frontiers of digital quantum simulations, including efficient simulations of fermionic systems [3], which become accessible when combining high two-qubit gate fidelities with highly nonlocal connectivity.

[1] Evered et al., Nature 645, 341–347 (2025).

[2] Bluvstein et al., Nature 649, 39–46 (2026)

[3] Maskara et al., arXiv:2509.08898 (2025)