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arXiv:2509.24766

Demonstration of quantum error detection in a silicon quantum processor

Chunhui Zhang, Chunhui Li, Zhen Tian, Yanfeng Jiang, Feng Xu, Shihang Zhang, Hao Wang, Yuning Zhang, Bai, Xuesong, Zhao, Baolong, Yifei Zhang, Shu Huan, Liu, Jiaze, Wu, Kunrong, Huang, Chao, Shi, Keji, Meiling Duan, Xin Tao, Peihao Huang, Tianluo Pan, Song Liu, Wang, Guanyong, Guangchong Hu, Yu He, Dapeng Yu

Published Sep 29, 2025• 0 citations
arXivHTMLPDF

Abstract

Quantum error detection is essential in realizing large-scale universal quantum computation, especially for quantum error correction (QEC). However, key elements for FTQC have yet to be realized in silicon qubits. Here, we demonstrate quantum error detection on a donor-based silicon quantum processor comprising four-nuclear spin qubits and one electron spin as an auxiliary qubit. The entanglement capability of this system is validated through the establishment of two-qubit Bell state entanglement between the nuclear spins and the generation of a four-qubit Greenberger-Horne-Zeilinger (GHZ) state, achieving a GHZ state fidelity of 88.5(2.3)%. Furthermore, by executing a four-qubit error detection circuit with the stabilizers, we successfully detect arbitrary single-qubit errors. The encoded Bell state entanglement information is recovered by performing the Pauli-frame update (PFU) via postprocessing. Based on the detected errors, we identify strongly biased noise in our system. Our results mark a significant advance toward FTQC in silicon spin qubits.

DOI
10.48550/arxiv.2509.24766

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