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arXiv · 2502.09542

Constant-Overhead Fault-Tolerant Bell-Pair Distillation using High-Rate Codes

J. Pablo Bonilla Ataides·Hengyun Zhou·Qian Xu·Gefen Baranes·Bikun Li·Mikhail D. Lukin·Liang Jiang
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Abstract

We present a fault-tolerant Bell-pair distillation scheme achieving constant overhead through high-rate quantum low-density parity-check (qLDPC) codes. Our approach maintains a constant distillation rate equal to the code rate while requiring no additional overhead beyond the physical qubits of the code. Full circuit-level analysis demonstrates fault-tolerance for input Bell pair infidelities below a threshold $\sim 10\%$, readily achievable with near-term capabilities. Unlike previous proposals, our scheme keeps the output Bell pairs encoded in qLDPC codes at each node, eliminating un-encoding overhead and enabling direct use in distributed quantum applications through recent advances in qLDPC computation. These results establish qLDPC-based distillation as a practical route toward resource-efficient quantum networks and distributed quantum computing.

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J. Pablo Bonilla Ataides, Hengyun Zhou, Qian Xu, Gefen Baranes, Bikun Li, Mikhail D. Lukin, Liang Jiang. 2025-02-13. Constant-Overhead Fault-Tolerant Bell-Pair Distillation using High-Rate Codes. https://doi.org/10.1103/s39k-r2kq

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