Criticality-enhanced quantum sensor at finite temperature
Abstract
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 employed as a quantum sensor to estimate parameters of interest in the Dicke model which experiences a thermodynamic phase transition. It is revealed that the thermodynamic criticality of the Dicke model can significantly improve the sensing precision. Enriching the scope of quantum critical metrology, our finding provides a possibility to realize highly sensitive quantum sensing without cooling.
- Publication:
-
Physical Review A
- Pub Date:
- August 2021
- DOI:
- 10.1103/PhysRevA.104.022612
- arXiv:
- arXiv:2110.07824
- Bibcode:
- 2021PhRvA.104b2612W
- Keywords:
-
- Quantum Physics
- E-Print:
- Phys. Rev. A 104,022612 (2021)