论文标题
以半设备独立的方式量化多部分量子纠缠
Quantifying Multipartite Quantum Entanglement in a Semi-Device-Independent Manner
论文作者
论文摘要
我们提出了两种独立的方法，能够在实验上量化未知的多部分量子纠缠，其中必须事先知道的唯一信息是量子维度，而扮演关键作用的概念是贝尔的不平等。具体而言，使用多部分钟形不平等的非平稳性，我们获得了有关目标量子状态纯度的有用信息。结合对目标状态和纯产品状态之间最大重叠的估计以及我们将证明的纠缠几何措施的连续特性，有关纯度的信息使我们能够为此纠缠措施提供下限。此外，我们表明，上述结果的不同组合也将纠缠相对熵的下限转换为一个下限。作为演示，我们将方法应用于具有MABK不平等的5正确量子系统，并表明，如果铃铛值大于3.60，则可以获得有用的下限，如果铃铛相对熵的铃声大于3.80大于3.80，则可以给出纠缠的几何测量。
We propose two semi-device-independent approaches that are able to quantify unknown multipartite quantum entanglement experimentally, where the only information that has to be known beforehand is quantum dimension, and the concept that plays a key role is nondegenerate Bell inequalities. Specifically, using the nondegeneracy of multipartite Bell inequalities, we obtain useful information on the purity of target quantum state. Combined with an estimate of the maximal overlap between the target state and pure product states and a continuous property of the geometric measure of entanglement we shall prove, the information on purity allows us to give a lower bound for this entanglement measure. In addition, we show that a different combination of the above results also converts to a lower bound for the relative entropy of entanglement. As a demonstration, we apply our approach on 5-partite qubit systems with the MABK inequality, and show that useful lower bounds for the geometric measure of entanglement can be obtained if the Bell value is larger than 3.60, and those for the relative entropy of entanglement can be given if the Bell value is larger than 3.80, where the Tsirelson bound is 4.
