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arXiv · 2504.08529

Temperature and non-Markovian parameter estimation in quantum Brownian motion

João C. P. Porto·Carlos H. S. Vieira·Irismar G. da Paz·Pedro R. Dieguez·Lucas S. Marinho
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Abstract

We investigate a quantum metrological protocol operating in a non-Markovian environment by employing the quantum Brownian motion (QBM) model, in which the system is linearly coupled to a reservoir of harmonic oscillators. Specifically, we use a position-momentum (PM) correlated Gaussian state as a probe to examine how memory effects influence the evolution of the system's covariance matrix in the weak coupling regime under both high- and low-temperature conditions. To confirm the presence of non-Markovian behavior, we apply two well-established non-Markovianity quantifiers. Furthermore, we estimate both the channel's sample temperature and its non-Markovianity witness parameter. Our results demonstrate that non-Markovianity and PM correlations can jointly be valuable resources to enhance metrological performance.

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João C. P. Porto, Carlos H. S. Vieira, Irismar G. da Paz, Pedro R. Dieguez, Lucas S. Marinho. 2025-04-11. Temperature and non-Markovian parameter estimation in quantum Brownian motion. https://doi.org/10.1103/c87r-22mn

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