发表机构
National University of Singapore; RIKEN Hakubi Research Team, RIKEN Pioneering Research Institute (PRI) and RIKEN Center for Quantum Computing (RQC); Centre for Quantum Technologies（新加坡国立大学; 理化学研究所惠比研究团队、理学前瞻性研究机构及理子量子计算中心; 量子技术中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文通过细化Regula和Tomamichel的剩余哈希引理，改进量子密钥分发的隐私放大界，在有限块体制下从相同实验数据中提取更多密钥，优于熵累积技术。
AI 中文摘要
从量子密钥分发运行中可获得的密钥量既取决于物理观测到的错误率，也取决于用于认证安全性的数学界。对于有限数据集，保守的界迫使使用者丢弃潜在可用密钥的相当大一部分。在此，我们进一步细化和扩展了通过Regula和Tomamichel最近的剩余哈希引理[arXiv:2603.04493]可实现的隐私放大界，并将其纳入基于熵不确定性关系的量子密钥分发安全性分析中。这改善了有限块体制下的最先进密钥率，在不改变协议的情况下，从相同的实验数据中认证出更多秘密密钥，并优于基于熵累积的技术。结果说明了更精确的数学估计如何能直接增加量子通信系统的可用输出。
英文摘要
The amount of secret key that can be obtained from a quantum key distribution run depends on both the physically observed error rates and the mathematical bounds used to certify security. For finite datasets, conservative bounds force users to discard a substantial fraction of the potentially available key. Here we further refine and extend the privacy amplification bounds achievable through the recent leftover hash lemma of Regula and Tomamichel [arXiv:2603.04493] and incorporate them into the security analysis of quantum key distribution based on entropic uncertainty relations. This improves on state-of-the-art key rates in finite-block regimes, certifying more secret key from the same experimental data without changes to the protocol, and outperforming techniques based on entropy accumulation. The results illustrate how sharper mathematical estimates can directly increase the usable output of a quantum communication system.
Comments14+13 pages
