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Quantum Discord and Maxwell's Demons

Wojciech Hubert Zurek
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Abstract

Quantum discord was proposed as an information theoretic measure of the ``quantumness'' of correlations. I show that discord determines the difference between the efficiency of quantum and classical Maxwell's demons -- that is, entities that can or cannot measure nonlocal observables or carry out conditional quantum operations -- in extracting work from collections of correlated quantum systems.

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Wojciech Hubert Zurek. 2003-01-23. Quantum Discord and Maxwell's Demons. https://doi.org/10.1103/physreva.67.012320

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