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arXiv · 2305.08397

Global quantum thermometry based on the optimal biased bound

Shoukang Chang·Wei Ye·Xuan Rao·Huan Zhang·Liqing Huang·Mengmeng Luo·Yuetao Chen·Qiang Ma·Shaoyan Gao
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Abstract

Thermometry is a fundamental parameter estimation problem which is crucial in the development process of natural sciences. One way to solve this problem is to the extensive used local thermometry theory, which makes use of the classical and quantum Cram\'er-Rao bound as benchmarks of thermometry precision. However, such a thermometry theory can only be used for decreasing temperature fluctuations around a known temperature value and hardly tackle the precision thermometry problem over a wide temperature range. For this reason, we derive two basic bounds on thermometry precision in the global setting and further show their thermometry performance by two specific applications, i.e., noninteracting spin-1/2 gas and a general N-level thermal equilibrium quantum probe.

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Shoukang Chang, Wei Ye, Xuan Rao, Huan Zhang, Liqing Huang, Mengmeng Luo, Yuetao Chen, Qiang Ma, Shaoyan Gao. 2023-05-15. Global quantum thermometry based on the optimal biased bound. https://arxiv.org/abs/2305.08397

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