Quantum entanglement is a fundamental property of coherent quantum states and an essential resource for quantum computing¹. In large-scale quantum systems, the error accumulation requires concepts for quantum error correction. A first step toward error correction is the creation of genuinely multipartite entanglement, which has served as a performance benchmark for quantum computing platforms such as superconducting circuits^2,3, trapped ions⁴ and nitrogen-vacancy centres in diamond⁵. Among the candidates for large-scale quantum computing devices, silicon-based spin qubits offer an outstanding nanofabrication capability for scaling-up. Recent studies demonstrated improved coherence times^6,7,8, high-fidelity all-electrical control^{9,10,11,12,13}, high-temperature operation^14,15 and quantum entanglement of two spin qubits^9,11,12. Here we generated a three-qubit Greenberger–Horne–Zeilinger state using a low-disorder, fully controllable array of three spin qubits in silicon. We performed quantum state tomography¹⁶ and obtained a state fidelity of 88.0%. The measurements witness a genuine Greenberger–Horne–Zeilinger class quantum entanglement that cannot be separated into any biseparable state. Our results showcase the potential of silicon-based spin qubit platforms for multiqubit quantum algorithms.

量子纠缠是相干量子态的基本属性，也是量子计算的重要资源¹。在大规模量子系统中，误差累积需要量子纠错的概念。纠错的第一步是创建真正的多方纠缠，它已作为量子计算平台的性能基准，例如超导电路^2,3、捕获的离子⁴和金刚石中的氮空位中心⁵。在大规模量子计算设备的候选者中，基于硅的自旋量子比特提供了出色的放大纳米加工能力。最近的研究表明，一致性时间有所改善^6,7,8, 高保真全电控制^{9,10,11,12,13}，高温操作^14,15和两个自旋量子比特的量子纠缠^9,11,12。在这里，我们使用硅中三个自旋量子比特的低无序、完全可控阵列生成了一个三量子比特 Greenberger-Horne-Zeilinger 状态。我们进行了量子态断层扫描¹⁶并获得了 88.0% 的状态保真度。测量见证了真正的 Greenberger-Horne-Zeilinger 级量子纠缠，它不能被分离成任何可分离的状态。我们的结果展示了基于硅的自旋量子位平台在多量子位量子算法中的潜力。