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arXiv · 2207.10742

Operational significance of nonclassicality in nonequilibrium Gaussian quantum thermometry

Safoura S. Mirkhalaf·Mohammad Mehboudi·Zohre Nafari Qaleh·Saleh Rahimi-Keshari
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Abstract

We provide new operational significance of nonclassicality in nonequilibrium temperature estimation of bosonic baths with Gaussian probe states and Gaussian dynamics. We find a bound on the thermometry performance using classical probe states. Then we show that by using nonclassical probe states, single-mode and two-mode squeezed vacuum states, one can profoundly improve the classical limit. Interestingly, we observe that this improvement can also be achieved by using Gaussian measurements. Hence, we propose a fully Gaussian protocol for enhanced thermometry, which can simply be realized and used in quantum optics platforms.

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Safoura S. Mirkhalaf, Mohammad Mehboudi, Zohre Nafari Qaleh, Saleh Rahimi-Keshari. 2022-07-21. Operational significance of nonclassicality in nonequilibrium Gaussian quantum thermometry. https://arxiv.org/abs/2207.10742

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