Inseparability criterion for continuous variable systems

  title={Inseparability criterion for continuous variable systems},
  author={Duan and Giedke and Cirac and Zoller},
  journal={Physical review letters},
  volume={84 12},
  • Duan, Giedke, Zoller
  • Published 17 August 1999
  • Mathematics
  • Physical review letters
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. 
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