论文标题
允许泄漏可以增加量子传输
Allowing leakage can increase quantum transmission
论文作者
论文摘要
纠缠和量子信息在于量子理论的根源。通常认为，当携带它们与环境相互作用时，这些非凡的资源会减少。相比之下，我们发现与其环境相关的系统可以提高其携带量子信息的能力。最大传输速率由量子通道容量给出。我们通过允许通道几乎所有量子信息泄漏到频道的环境中来提高通道的这种能力。我们从概念上和数字上解释了这一提升，这是由频道连贯信息中的两个字母级别的超级添加性引起的。这种超级添加性具有比以前已知的更大的幅度和质量更大的程度。我们的发现对量子密钥分布具有令人惊讶的含义：通过允许信息泄漏到窃听环境中，可以提高键分布的最大速率。
Entanglement and quantum information lie at the root of quantum theory. These remarkable resources are generally believed to diminish when systems carrying them interact with their environment. By contrast, we find that engaging a system with its environment can increases its ability to carry quantum information. The maximum rate of transmission is given by the quantum channel capacity. We counter-intuitively boost this capacity of a channel by allowing it to leak almost all quantum information to the channel's environment. We conceptually and numerically explain this boost to arise from two-letter level super-additivity in the channel's coherent information. Such super-additivity has a far larger magnitude and a qualitatively wider extent than previously known. Our findings have a surprising implication for quantum key distribution: maximum rates for key distribution can be boosted by allowing leakage of information to the eavesdropping environment.
