Operational significance of nonclassicality in nonequilibrium Gaussian quantum thermometry

• URL: http://arxiv.org/abs/2207.10742v2
• Date: Wed, 20 Sep 2023 12:23:59 GMT
• Title: Operational significance of nonclassicality in nonequilibrium Gaussian quantum thermometry
• Authors: Safoura S. Mirkhalaf, Mohammad Mehboudi, Zohre Nafari Qaleh, Saleh Rahimi-Keshari
• Abstract summary: We find a bound on the thermometry performance using classical probe states. We show that by using nonclassical probe states, single-mode and two-mode squeezed vacuum states, one can profoundly improve the classical limit.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• 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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