Single-qubit gates with errors at the 10⁻⁷ level

Demonstrates single-qubit Clifford gate errors of 1.5(4) × 10⁻⁷ (fidelity 99.999985%) in a ⁴³Ca⁺ hyperfine clock qubit, setting the world record for single-qubit gate fidelity in any platform. Uses microwave-driven gates in a cryogenic surface-electrode trap at the University of Oxford.

Key Results

• Single-qubit Clifford gate error: 1.5(4) × 10⁻⁷ (randomized benchmarking)
• Gate calibration errors suppressed below 10⁻⁸
• Fastest gate (4.4 μs): error 2.9(5) × 10⁻⁷
• Dominant error sources: qubit decoherence (T₂ ≈ 70 s), leakage, measurement
• Memory error < 10⁻⁴ for storage times up to ~50 ms
• Nearly an order of magnitude improvement over Harty et al. 2014

Links

• Journal: Physical Review Letters
• arXiv: 2412.04421

Zoo Links

• trapped-ion-qubit