# Extremality of Gaussian quantum states.

@article{Wolf2006ExtremalityOG, title={Extremality of Gaussian quantum states.}, author={Michael M. Wolf and Geza Giedke and Juan Ignacio Cirac}, journal={Physical review letters}, year={2006}, volume={96 8}, pages={ 080502 } }

We investigate Gaussian quantum states in view of their exceptional role within the space of all continuous variables states. A general method for deriving extremality results is provided and applied to entanglement measures, secret key distillation and the classical capacity of bosonic quantum channels. We prove that for every given covariance matrix the distillable secret key rate and the entanglement, if measured appropriately, are minimized by Gaussian states. This result leads to a clearer… Expand

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