A research team, which comprises Pan Jianwei, Zhu Xiaobo, and other scholars from the University of Science and Technology of China (USTC), leveraged the superconducting quantum processor, named 'Zuchongzhi 3.2', to successfully implement quantum error correction below the error threshold. This feat was accomplished on a surface code with a code distance of 7. Their work notably demonstrated a substantial decrease in logical error rates as the code distance was extended, marking a crucial milestone characterized by 'lower error rates beyond the threshold, enhanced correction capabilities, and greater accuracy'. Additionally, it paved the way for a novel approach termed 'all-microwave control'.

The cornerstone of realizing fault-tolerant universal quantum computers rests on the ability to curb qubit error rates through quantum error correction. Breaking through the 'error correction threshold' has emerged as a central focus in global quantum error correction research. Prior endeavors by USTC in 2022 and Google in 2023 fell short of surpassing this threshold. Although Google managed to achieve logical qubits operating below the threshold in February 2025, its technical methodology was not without constraints.

By the close of 2025, the USTC team unveiled an 'all-microwave quantum state leakage suppression architecture' and successfully demonstrated logical qubits on a surface code with a code distance of 7, with the system functioning below the error threshold. This innovative architecture boasts considerable benefits in terms of hardware efficiency and scalability, presenting a superior blueprint for the construction of million-qubit-scale quantum computers. The pertinent findings were published in Physical Review Letters on December 22.