Abstract
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.
- Received 14 January 2013
DOI:https://doi.org/10.1103/PhysRevLett.110.210502
© 2013 American Physical Society
