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arXiv · 2407.21618

Information flow-enhanced precision in collisional quantum thermometry

Taysa M. Mendonça·Diogo O. Soares-Pinto·Mauro Paternostro
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Abstract

We describe and analyze a quantum thermometer based on a multilayered collisional model. We propose a qubit system whose architecture provides significant sensitivity even for short interaction times between the ancillae that compose the thermometer probe and the system to be probed. The assessment of the flow of information taking place within the layered thermometer and between system and thermometer reveals that the tuning of the mutual backflow of information has a positive influence on the precision of thermometry, and helps unveiling the information-theoretic mechanisms behind the working principles of the proposed architecture.

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Taysa M. Mendonça, Diogo O. Soares-Pinto, Mauro Paternostro. 2024-07-31. Information flow-enhanced precision in collisional quantum thermometry. https://doi.org/10.1103/ymjl-hpm4

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