What it is
Quantinuum's Helios is a trapped-ion quantum processor built from 98 barium-137 hyperfine qubits in a quantum charge-coupled-device architecture, with a rotatable ion storage ring that gives every qubit all-to-all connectivity. Averaged across all operating zones, the system records single-qubit gate infidelity of 2.5x10^-5, two-qubit gate infidelity of 7.9x10^-4 (about 99.921% two-qubit fidelity), and state-preparation-and-measurement infidelity of 3.3x10^-4. On random circuit sampling, Helios ran circuits placed well beyond the reach of classical simulation.
Why it matters
Trapped ions have long held the fidelity record, but adding qubits usually degrades performance; Helios keeps error rates low at 98 qubits while preserving full connectivity, which cuts the routing overhead that limits fixed-lattice designs. Fidelity at this level is what error-corrected machines are built from, since logical qubits demand physical error rates comfortably below threshold. The authors note none of the 2.5x10^-5, 7.9x10^-4, or 3.3x10^-4 infidelities are fundamentally limited, leaving headroom to improve.
Underlined numbers link to their source. Every metric and quoted figure is listed under Sources and data below.
Filed underquantum computing, trapped ions, gate fidelity, error correction, Quantinuum
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