Critical Quantum Metrology with a Finite-Component Quantum Phase Transition
Physical systems close to a quantum phase transition exhibit a divergent susceptibility, suggesting that an arbitrarily high precision may be achieved by exploiting quantum critical systems as probes to estimate a physical parameter. However, such an improvement in sensitivity is counterbalanced by...
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Published in | Physical review letters Vol. 124; no. 12; p. 120504 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
United States
27.03.2020
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Online Access | Get more information |
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Summary: | Physical systems close to a quantum phase transition exhibit a divergent susceptibility, suggesting that an arbitrarily high precision may be achieved by exploiting quantum critical systems as probes to estimate a physical parameter. However, such an improvement in sensitivity is counterbalanced by the closing of the energy gap, which implies a critical slowing down and an inevitable growth of the protocol duration. Here, we design different metrological protocols that exploit the superradiant phase transition of the quantum Rabi model, a finite-component system composed of a single two-level atom interacting with a single bosonic mode. We show that, in spite of the critical slowing down, critical quantum optical probes can achieve a quantum-enhanced time scaling of the sensitivity in frequency-estimation protocols. |
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ISSN: | 1079-7114 |
DOI: | 10.1103/PhysRevLett.124.120504 |