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arXiv · 2407.20338

Realization of high-fidelity perfect entangler between remote superconducting quantum processors

Juan Song·Shuang Yang·Pei Liu·Hui-Li Zhang·Guang-Ming Xue·Zhen-Yu Mi·Wen-Gang Zhang·Fei Yan·Yi-Rong Jin·Hai-Feng Yu
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Abstract

Superconducting qubits, a promising candidate for universal quantum computing, currently face limitations in chip size due to reproducibility, wiring complexity, and packaging modes. Distributed quantum modules offer a viable strategy for constructing larger quantum information processing systems, though universal quantum gate operations between remote qubits have yet to be realized. Here, we demonstrate high-fidelity perfect entanglers between two remote superconducting quantum devices over 30 cm distance, leveraging the standing-wave modes in the coaxial cable connecting them. We achieve cross-entropy benchmarking (XEB) fidelities of $(99.15 \pm 0.02)\%$ and $(98.04 \pm 0.04)\%$ for CNOT and CZ gates, respectively, which are more efficient and universal than existing state transfer or feedback-based protocols. This advancement significantly enhances the feasibility of universal distributed quantum information processing, essential for the future development of large-scale quantum systems.

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Juan Song, Shuang Yang, Pei Liu, Hui-Li Zhang, Guang-Ming Xue, Zhen-Yu Mi, Wen-Gang Zhang, Fei Yan, Yi-Rong Jin, Hai-Feng Yu. 2024-07-29. Realization of high-fidelity perfect entangler between remote superconducting quantum processors. https://arxiv.org/abs/2407.20338

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