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arXiv · 1710.11586

Residual and Destroyed Accessible Information after Measurements

Rui Han·Gerd Leuchs·Markus Grassl
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Abstract

When quantum states are used to send classical information, the receiver performs a measurement on the signal states. The amount of information extracted is often not optimal due to the receiver's measurement scheme and experimental apparatus. For quantum non-demolition measurements, there is potentially some residual information in the post-measurement state, while part of the information has been extracted and the rest is destroyed. Here, we propose a framework to characterize a quantum measurement by how much information it extracts and destroys, and how much information it leaves in the residual post-measurement state. The concept is illustrated for several receivers discriminating coherent states.

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Rui Han, Gerd Leuchs, Markus Grassl. 2017-10-31. Residual and Destroyed Accessible Information after Measurements. https://doi.org/10.1103/physrevlett.120.160501

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