量子ビット操作精度で世界新記録を樹立（Oxford physicists set new world record for qubit operation accuracy）

2025-06-10 オックスフォード大学

Photograph of the Oxford University team’s ion trap chip. Credit: Dr Jochen Wolf and Dr Tom Harty.

＜関連情報＞

• https://www.ox.ac.uk/news/2025-06-10-oxford-physicists-set-new-world-record-qubit-operation-accuracy
• https://journals.aps.org/prl/accepted/10.1103/42w2-6ccy

10-7レベルの誤差を持つ単一量子ビットゲート Single-qubit gates with errors at the 10−7 level

M. C. Smith, A. D. Leu, K. Miyanishi, M. F. Gely, and D. M. Lucas
Physical Review Letters  Accepted: 19 May, 2025
DOI: https://doi.org/10.1103/42w2-6ccy

Abstract

We report the achievement of single-qubit gates with sub-part-per-million error rates, in a trapped-ion ⁴³Ca⁺ hyperfine clock qubit. We explore the speed/fidelity trade-off for gate times 4.4≤≤35⁢μs, and benchmark a minimum error per Clifford gate of 1.5⁢(4)×10⁻⁷. Calibration errors are suppressed to $ less than 10^{-8},⁢⁢⁢⁢⁢⁢⁢⁢⁢⁢⁢⁢⁢⁢⁢ℎ⁢⁢⁢⁢⁢(T_{2}$ s), leakage, and measurement as the dominant error contributions. The ion is held above a microfabricated surface-electrode trap which incorporates a chip-integrated microwave resonator for electronic qubit control; the trap is operated at room temperature without magnetic shielding.