Caltech physicists have created the largest neutral-atom quantum computer ever built, assembling a record-setting array of 6,100 qubits formed by cesium atoms trapped individually in optical tweezers. This breakthrough, published in Nature in 2025, represents a significant step toward scalable, error-corrected quantum computing.
The system achieves remarkable technical specifications: the qubits maintain quantum superposition for approximately 13 seconds—nearly ten times longer than previous neutral-atom tweezer systems—while individual qubit operations demonstrate 99.98% accuracy. The optical tweezer array includes roughly 12,000 sites, with over 6,100 trapping cesium atoms simultaneously using laser tweezers operating at near-infrared wavelengths that minimize decoherence from photon scattering.
Professor Manuel Endres, the principal investigator, emphasized the significance of this achievement: “This is an exciting moment for neutral-atom quantum computing. We can now see a pathway to large error-corrected quantum computers. The building blocks are in place.” The research demonstrates the ability to shuttle atoms hundreds of micrometers across the array with approximately 99.95% fidelity, crucial for effective error correction and quantum gate operations.
Compared to other quantum computing platforms, neutral atoms offer distinct advantages. While superconducting qubits from companies like IBM and Google achieve faster gate speeds but shorter coherence times (~100 μs), and trapped ions from IonQ and Quantinuum offer higher gate fidelities (>99.5%) but limited qubit counts, neutral atoms excel in scalability and coherence duration.
The Caltech team’s next steps focus on implementing quantum error correction protocols using this large-scale platform. Recent demonstrations have shown neutral-atom processors executing multiple rounds of surface-code quantum error correction cycles, employing machine learning for error decoding and managing atom loss while performing logical gates on encoded qubits.
This achievement marks a practical roadmap for constructing large-scale neutral-atom quantum computers with hundreds of thousands of qubits needed for fault-tolerant, error-corrected quantum computing. The combination of high fidelity, long coherence, and precise controllability at unprecedented scale positions neutral atoms as a leading contender in the race toward practical quantum advantage.
