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arXiv · 2004.05331

The information capacity of entanglement-assisted continuous variable measurement

A. S. Holevo·A. A. Kuznetsova
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Abstract

The present paper is devoted to investigation of the entropy reduction and entanglement-assisted classical capacity (information gain) of continuous variable quantum measurements. These quantities are computed explicitly for multimode Gaussian measurement channels. For this we establish a fundamental property of the entropy reduction of a measurement: under a restriction on the second moments of the input state it is maximized by a Gaussian state (providing an analytical expression for the maximum). In the case of one mode, the gain of entanglement assistance is investigated in detail.

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A. S. Holevo, A. A. Kuznetsova. 2020-04-11. The information capacity of entanglement-assisted continuous variable measurement. https://doi.org/10.1088/1751-8121%2Faba91f

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