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arXiv · 1805.01477

Thermodynamic work cost of quantum estimation protocols

Patryk Lipka-Bartosik·Rafal Demkowicz-Dobrzanski
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Abstract

We discuss thermodynamic work cost of various stages of a quantum estimation protocol: probe and memory register preparation, measurement and extraction of work from post-measurement states. We consider both (i) a multi-shot scenario, where average work is calculated in terms of the standard Shannon entropy and (ii) a single-shot scenario, where deterministic work is expressed in terms of min- and max-entropies. We discuss an exemplary phase estimation protocol where estimation precision is optimized under a fixed work credit (multi-shot) or a total work cost (single-shot). In the multi-shot regime precision is determined using the concept of Fisher information, while in the single-shot case we advocate the use of confidence intervals as only they can provide a meaningful and reliable information in a single-shot experiment, combining naturally with the the concept of deterministic work.

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Patryk Lipka-Bartosik, Rafal Demkowicz-Dobrzanski. 2018-05-03. Thermodynamic work cost of quantum estimation protocols. https://doi.org/10.1088/1751-8121/aae664

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