SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
Phys Rev Lett. 2013 May 24;110(21):210502. doi: 10.1103/PhysRevLett.110.210502. Epub 2013 May 21.
We derive reliable entanglement witnesses for coarse-grained measurements on continuous variable systems. These witnesses never return a "false positive" for identification of entanglement, under any degree of coarse graining. We show that even in the case of Gaussian states, entanglement witnesses based on the Shannon entropy can outperform those based on variances. We apply our results to experimental identification of spatial entanglement of photon pairs.
我们为连续变量系统的粗粒测量推导出可靠的纠缠证据。在任何程度的粗粒化下，这些证据对于纠缠的识别永远不会返回“假阳性”。我们表明，即使对于高斯态，基于香农熵的纠缠证据也可以优于基于方差的纠缠证据。我们将我们的结果应用于光子对空间纠缠的实验识别。
