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arXiv · 2102.01981

Accessible information of a general quantum Gaussian ensemble

A. S. Holevo
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Abstract

Accessible information, which is a basic quantity in quantum information theory, is computed for a general quantum Gaussian ensemble under certain "threshold condition". It is shown that the maximizing measurement is Gaussian, constituting a far-reaching generalization of the optical heterodyning. This substantially extends the previous result concerning the gauge-invariant case, even for a single bosonic mode.

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A. S. Holevo. 2021-02-03. Accessible information of a general quantum Gaussian ensemble. https://doi.org/10.1063/5.0048112

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