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arXiv · 1608.04305

On quantum additive Gaussian noise channels

Martin Idel·Robert Koenig
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Abstract

We give necessary and sufficient conditions for a Gaussian quantum channel to have a dilation involving a passive, i.e., number-preserving unitary. We then establish a normal form of such channels: any passively dilatable channel is the result of applying passive unitaries to the input and output of a Gaussian additive channel. The latter combine the state of the system with that of the environment by means of a multi-mode beamsplitter.

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Martin Idel, Robert Koenig. 2016-08-15. On quantum additive Gaussian noise channels. https://arxiv.org/abs/1608.04305

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