Bergh Bjarne, Gärttner Martin
Kirchhoff-Institut für Physik, Universität Heidelberg, Im Neuenheimer Feld 227, 69120 Heidelberg, Germany.
Physikalisches Institut, Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany.
Phys Rev Lett. 2021 May 14;126(19):190503. doi: 10.1103/PhysRevLett.126.190503.
Entanglement is not only the resource that fuels many quantum technologies but also plays a key role for some of the most profound open questions of fundamental physics. Experiments controlling quantum systems at the single quantum level may shed light on these puzzles. However, measuring, or even bounding, entanglement experimentally has proven to be an outstanding challenge, especially when the prepared quantum states are mixed. We use entropic uncertainty relations for bipartite systems to derive measurable lower bounds on distillable entanglement. We showcase these bounds by applying them to physical models realizable in cold-atom experiments. The derived entanglement bounds rely on measurements in only two different bases and are generically applicable to any quantum simulation platform.
纠缠不仅是推动许多量子技术发展的资源，而且在一些最深刻的基础物理开放性问题中也起着关键作用。在单量子水平上控制量子系统的实验可能会为这些难题带来启示。然而，通过实验测量甚至界定纠缠已被证明是一项极具挑战性的任务，尤其是当制备的量子态是混合态时。我们利用二分系统的熵不确定性关系来推导可提纯纠缠的可测量下限。我们通过将这些下限应用于冷原子实验中可实现的物理模型来展示它们。推导得出的纠缠下限仅依赖于在两个不同基下的测量，并且一般适用于任何量子模拟平台。
