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arXiv · 2502.02897

High-fidelity initialization a logical qubit with multiple injections

Zhi-Cheng He·Zheng-Yuan Xue
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Abstract

Quantum error correction represents a significant advancement in large-scale quantum computing. However, achieving fault-tolerant implementations of non-Clifford logical gates with reduced overhead remains a challenge in the popular surface code strategy. Recent advances have underscored the need for a substantial code distance to attain complete fault tolerance. Here, we introduce a continuous fault-tolerant scheme for non-Clifford logical gates via multiple injections. Unlike existing protocols that focus on a single logical chain, our approach utilizes multiple logical chains, each can employ the same or different logical rotation angles, to initialize a non-Clifford state. Compared to previous efforts, our protocol significantly alleviates the challenges associated with the requirement for a large code distance and reduces the corresponding resource overhead, making it more feasible to be implemented in current mid-scale chips via the surface code strategy.

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Zhi-Cheng He, Zheng-Yuan Xue. 2025-02-05. High-fidelity initialization a logical qubit with multiple injections. https://doi.org/10.1103/physreva.111.052419

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