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arXiv · 2608.13090

Robust controlled-Z gate for Rydberg atoms based on level-crossing-free echoing rapid adiabatic passage

Yichi Zhang·Zhenqi Bai·Xu Zhao·Hongyan Fan·Ximo Wang·Tiecheng Wang
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Abstract

We propose a controlled-Z gate scheme for Rydberg atoms based on level-crossing-free echoing rapid adiabatic population transfer. We design antisymmetric Rabi frequency pulses and symmetric detuning pulses, enabling the system to completely avoid level-crossing points throughout the evolution, and the dynamical phase is naturally eliminated by the time-reversal symmetry of the double-pulse sequence. We incorporate dissipative effects through the Lindblad master equation. The numerical simulation yields a two-qubit CZ gate fidelity of 0.9999. When the Rabi-frequency fluctuation is within $\pm 2\%$, and the detuning offset is within $\pm 1\%$, the fidelity can still remain above 0.999. Under the same dissipative model, the three-qubit CCZ gate achieves a fidelity of 0.999. When a single-parameter fluctuation does not exceed $\pm 3\%$, the fidelity is always higher than 0.997. Our scheme requires no laser phase jumps or fast switching operations. The zero-area pulse structure suppresses first-order intensity noise, and the symmetric double-pulse sequence avoids spatially resolved laser switching, making it suitable for parallel gate operations in large-scale neutral-atom arrays.

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Yichi Zhang, Zhenqi Bai, Xu Zhao, Hongyan Fan, Ximo Wang, Tiecheng Wang. 2026-08-13. Robust controlled-Z gate for Rydberg atoms based on level-crossing-free echoing rapid adiabatic passage. https://arxiv.org/abs/2608.13090

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