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arXiv · 1001.2225

Separability Criterion for One-Sided Gaussian Channels

Jason Hoelscher-Obermaier·Peter van Loock
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Abstract

We show that the following nontrivial necessary precondition for an entanglement evolution equation for pure Gaussian states under one-sided Gaussian channels holds. Suppose a Gaussian quantum channel acts on one mode of a pure entangled multi-mode Gaussian input state. Then, for a fixed channel, either all output states are entangled or none of them are. In other words, if the input state is Gaussian, pure and entangled, the separability after a one-sided Gaussian quantum channel does not depend on the input state, but only on the channel. Furthermore, a simple linear-algebraic separability criterion allows to decide whether a given channel destroys the entanglement of pure entangled input states or leaves them entangled.

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Jason Hoelscher-Obermaier, Peter van Loock. 2010-01-13. Separability Criterion for One-Sided Gaussian Channels. https://arxiv.org/abs/1001.2225

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