私有关联可证明传感能力
Private Correlations Certify Sensing Capability
- Perimeter Institute for Theoretical Physics
- University of Waterloo（滑铁卢大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究提出私有关联可作为分布式传感的计量资源，证明编码基中正私有信息能为局部可访问传感能力提供定量下界，且仅经典关联无法实现类似保证。
AI中文摘要：
我们证明，在二分量子态中的私有关联可构成分布式传感的计量资源，该传感由一方到另一方的可能存在噪声的信道辅助。我们以一个具有可蒸馏密钥但局部可访问传感性能较差的例子入手，表明辅助信道可大幅提升其性能。随后我们证明了一个一般性定理，即编码基中的正私有信息可在辅助后为局部可访问的传感能力提供定量下界。我们进一步表明，仅经典关联无法提供类似保证，而在不存在辅助子系统时，基于私有信息的保证会退化为基于纠缠的保证。最后，在信道框架中，我们证明当具有正私有信息的信道与合适的辅助信道配对时，可实现非零的局部可访问灵敏度。
英文摘要：
We show that private correlations in a bipartite quantum state constitute a metrological resource for distributed sensing assisted by a possibly noisy channel from one party to the other. We begin with an example with distillable secret key but poor locally accessible sensing performance and show that an assisting channel substantially improves its performance. We then show that any shared state yielding positive private information can serve as a sensing resource after appropriate local coherent processing, and derive a quantitative lower bound on the locally accessible sensing capability after assistance. We further show that classical correlations alone provide no analogous guarantee. Finally, in a channel formulation, we show that a channel with positive private information allows nonzero locally accessible sensitivity when paired with a suitable assisting channel.
