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arXiv · 0811.3128

A No-Go Theorem for Gaussian Quantum Error Correction

Julien Niset·Jaromir Fiurasek·Nicolas J. Cerf
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Abstract

It is proven that Gaussian operations are of no use for protecting Gaussian states against Gaussian errors in quantum communication protocols. Specifically, we introduce a new quantity characterizing any single-mode Gaussian channel, called entanglement degradation, and show that it cannot decrease via Gaussian encoding and decoding operations only. The strength of this no-go theorem is illustrated with some examples of Gaussian channels.

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Julien Niset, Jaromir Fiurasek, Nicolas J. Cerf. 2008-11-19. A No-Go Theorem for Gaussian Quantum Error Correction. https://doi.org/10.1103/physrevlett.102.120501

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