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arXiv · 2412.04421

Single-qubit gates with errors at the $10^{-7}$ level

M. C. Smith·A. D. Leu·K. Miyanishi·M. F. Gely·D. M. Lucas
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Abstract

We report the achievement of single-qubit gates with sub-part-per-million error rates, in a trapped-ion $^{43}$Ca$^{+}$ hyperfine clock qubit. We explore the speed/fidelity trade-off for gate times $4.4\leq t_{g}\leq35~\mu$s, and benchmark a minimum error per Clifford gate of $1.5(4) \times 10^{-7}$. Calibration errors are suppressed to $< 10^{-8}$, leaving qubit decoherence ($T_{2}\approx 70$ 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.

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M. C. Smith, A. D. Leu, K. Miyanishi, M. F. Gely, D. M. Lucas. 2024-12-05. Single-qubit gates with errors at the $10^{-7}$ level. https://doi.org/10.1103/42w2-6ccy

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