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arXiv · 2306.01307

Low-crosstalk optical addressing system for atomic qubits based on multiple objectives and acousto-optic deflectors

Yi-Long Chen·Rui-Rui Li·Ran He·Shu-Qian Chen·Wen-Hao Qi·Jin-Ming Cui·Yun-Feng Huang·Chuan-Feng Li·Guang-Can Guo
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Abstract

Large-scale programmable trapped ion hardware, featuring high gate fidelity and long coherence times, is promising for realizing a practical fault-tolerant quantum computer (FTQC). However, individual addressing (IA) methods, which are important for implementing programmable gates in near-term quantum devices, can lead to undesired errors between the target ions and neighboring ions. In this work, we present a low-crosstalk optical addressing system based on multiple optical objectives and acousto-optic deflectors (AODs) with a symmetrical configuration. Two counter-propagating Raman operation beams are both tightly focused, generating an overlapping spot with a waist radius of approximately $1~\upmu\mathrm{m}$, to address the target ion. As a result, IA crosstalk, characterized by Rabi rate crosstalk on the spectator ion, is measured to be $1.19(5)\times10^{-3}$, with the two ions separated by approximately 5.5~$\upmu\mathrm{m}$. This low-crosstalk optical addressing system holds promise for high-fidelity entangling operations, and the symmetrically-configured AODs in our method can be readily extended to two dimensions to address a two-dimensional ion crystal.

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Yi-Long Chen, Rui-Rui Li, Ran He, Shu-Qian Chen, Wen-Hao Qi, Jin-Ming Cui, Yun-Feng Huang, Chuan-Feng Li, Guang-Can Guo. 2023-06-02. Low-crosstalk optical addressing system for atomic qubits based on multiple objectives and acousto-optic deflectors. https://arxiv.org/abs/2306.01307

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