Abstract
An inseparability criterion based on the total variance of a pair of Einstein-Podolsky-Rosen type operators is proposed for continuous variable systems. The criterion provides a sufficient condition for entanglement of any two-party continuous variable states. Furthermore, for all Gaussian states, this criterion turns out to be a necessary and sufficient condition for inseparability.
- Received 17 August 1999
DOI:https://doi.org/10.1103/PhysRevLett.84.2722
©2000 American Physical Society