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arXiv · 2008.09065

Channels, measurements and post-selection in quantum thermodynamics

Tom Purves·Tony Short
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Abstract

We analyse the benefit, in terms of extracting work, of having a single use of a quantum channel or measurement in quantum thermodynamics. This highlights a connection between unital and catalytic channels, and some subtleties concerning the conditional work cost of implementing a measurement given that a certain result was obtained. We also consider post-selected measurements, and show that any non-trivial post-selection leads to an unbounded work benefit.

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Tom Purves, Tony Short. 2020-08-20. Channels, measurements and post-selection in quantum thermodynamics. https://doi.org/10.1103/physreve.104.014111

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