Chinese researchers have become the second team worldwide—and the first outside the United States—to cross the fault-tolerant threshold in quantum error correction, a pivotal milestone that determines whether quantum computers can operate reliably at scale.

Led by Pan Jianwei at the University of Science and Technology of China (USTC), the team demonstrated on their superconducting prototype Zuchongzhi 3.2 that logical error rates decrease significantly as code distance increases, using a surface code with distance seven.

The breakthrough employs an innovative “all-microwave quantum state leakage suppression architecture” on the 107-qubit processor, achieving an error-suppression factor of 1.4—verifying operation below the threshold where correction strengthens stability rather than undermines it.

Published last week as a cover paper and Editors’ Suggestion in Physical Review Letters, the work offers a potentially more efficient “all-microwave control” pathway compared to Google’s hardware-intensive methods. Crossing the threshold is widely regarded as the dividing line between experimental prototypes and practical quantum systems.

This advance builds on USTC’s March 2025 Zuchongzhi 3.0 (105 qubits), which set superconducting quantum advantage records. Experts say the achievement accelerates China’s drive in next-generation computing amid intensifying global competition.