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arXiv · 2511.22202

Optimal Control for Rydberg multi-qubit operations

Hossein Abedi·Mohammadsadegh Khazali·Klaus Mølmer
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Abstract

Quantum computing algorithms can be decomposed into a universal set of elementary one- and two-qubit gates. Different physical implementations of quantum computing, however, employ interactions that permit direct conditional dynamics on multiple qubits in a single step. In this work, we leverage quantum optimal control techniques to design single continuous laser pulses that implement multi-qubit controlled-phase, -NOT and -swap (Fredkin) gates on Rydberg atom quantum processors. The identification of robust multi-qubit operations leads to reduced operation time and less decoherence, and the control field provides continuous protection of the atoms from environmental noise. Notably, we find that the controlled-swap (Fredkin) gate, implemented using this approach achieves 99.74\% fidelity while accounting for imperfections such as spontaneous emission, laser fluctuations, and Doppler dephasing.

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Hossein Abedi, Mohammadsadegh Khazali, Klaus Mølmer. 2025-11-27. Optimal Control for Rydberg multi-qubit operations. https://arxiv.org/abs/2511.22202

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