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arXiv · 1907.04704

Quantum bath statistics tagging

Donato Farina·Vasco Cavina·Vittorio Giovannetti
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Abstract

The possibility of discriminating the statistics of a thermal bath using indirect measurements performed on quantum probes is presented. The scheme relies on the fact that, when weakly coupled with the environment of interest, the transient evolution of the probe toward its final thermal configuration, is strongly affected by the fermionic or bosonic nature of the bath excitations. Using figures of merit taken from quantum metrology such as the Holevo-Helstrom probability of error and the Quantum Chernoff bound, we discuss how to achieve the greatest precision in this statistics tagging procedure, analyzing different models of probes and different initial preparations and by optimizing over the time of exposure of the probe.

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Donato Farina, Vasco Cavina, Vittorio Giovannetti. 2019-07-10. Quantum bath statistics tagging. https://doi.org/10.1103/physreva.100.042327

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