Gaussification and entanglement distillation of continuous-variable systems: a unifying picture.

  title={Gaussification and entanglement distillation of continuous-variable systems: a unifying picture.},
  author={Earl T. Campbell and Jens Eisert},
  journal={Physical review letters},
  volume={108 2},
Distillation of entanglement using only Gaussian operations is an important primitive in quantum communication, quantum repeater architectures, and distributed quantum computing. Existing distillation protocols for continuous degrees of freedom are only known to converge to a Gaussian state when measurements yield precisely the vacuum outcome. In sharp contrast, non-Gaussian states can be deterministically converted into Gaussian states while preserving their second moments, albeit by usually… 

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