# Criticality-enhanced quantum sensor at finite temperature

@article{Wu2021CriticalityenhancedQS, title={Criticality-enhanced quantum sensor at finite temperature}, author={Wei Wu and Chuan Shi}, journal={Physical Review A}, year={2021} }

Conventional criticality-based quantum metrological schemes work only at zero or very low temperature because the quantum uncertainty around the quantum phase-transition point is generally erased by thermal fluctuations with the increase of temperature. Such an ultralow-temperature requirement severely restricts the development of quantum critical metrology. In this paper, we propose a thermodynamic-criticality-enhanced quantum sensing scenario at finite temperature. In our scheme, a qubit is…

## One Citation

Effects of counter-rotating-wave terms on the noisy frequency estimation

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We investigate the problem of estimating the tunneling frequency of a two-level atomic system embedded in a dissipative environment by employing a numerically rigorous hierarchical equations of…

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