发表机构
The University of Illinois at Urbana-Champaign; Duke University; University of Chicago; Argonne National Laboratory（伊利诺伊大学厄巴纳-香槟分校; 杜克大学; 芝加哥大学; 阿贡国家实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究设计了抗失谐的里德伯纠缠ZZ门，将一阶失谐误差归为单量子比特Z旋转并由回波序列消除，大幅放宽了对激光频率稳定性等的要求，推动中性原子实用容错量子计算发展。
AI 中文摘要
中性原子阵列中基于里德伯的两量子比特门保真度主要受激光强度不均匀性以及失谐误差的限制，这些失谐误差源于频率校准错误、背景场漂移、中间态光移和多普勒频移。量子最优控制可抑制前者，但任何脉冲都无法使受控-Z门对失谐具有一阶不敏感性。本文表明，通过设计里德伯门脉冲，将所有一阶失谐误差归为单量子比特Z旋转，而回波序列可消除这些误差，即可规避该障碍。所得的最大纠缠ZZ门对任一原子的任意失谐均无一阶响应，在比此前门设计宽得多的单原子失谐范围内，其失保真度保持在10⁻³以下。我们进一步表明，大部分残留误差由计算子空间外的布居主导，该布居可转化为可预告的擦除错误。我们的结果大幅降低了激光频率稳定性、强度均匀性、场校准及原子温度的要求，推动中性原子实用容错量子计算的发展。
英文摘要
Rydberg-based two-qubit gate fidelities in neutral atom arrays are limited chiefly by laser intensity inhomogeneity and by detuning errors from frequency miscalibration, background-field drift, intermediate state light shift and Doppler shifts. Quantum optimal control can suppress the former, but no pulse can render a controlled-Z gate first-order insensitive to detuning. Here we show that this obstruction can be circumvented by designing Rydberg gate pulses with every leading-order detuning error relegated to single-qubit Z-rotations, which an echoed sequence removes. The resulting maximally-entangling ZZ gate has no leading-order response to arbitrary detunings on either atom, maintaining an infidelity below $10^{-3}$ within a much wider range of single-atom detunings than the time-optimal gates. We further show that a large fraction of residual error is dominated by population outside the computational subspace, which can be converted into heralded erasures. Our results significantly reduce the requirements on laser frequency stability and intensity homogeneity, field calibration and atomic temperature toward practical fault-tolerant quantum computing with neutral atoms.
Comments11 pages, 9 figures
