Critical Quantum Metrology with a Finite-Component Quantum Phase Transition

Area of Science:

• Quantum physics
• Quantum metrology
• Quantum optics

Background:

• Quantum phase transitions lead to divergent susceptibility, enabling high precision measurements.
• Critical slowing down near phase transitions typically increases protocol duration, limiting practical applications.

Purpose of the Study:

• To design metrological protocols utilizing the superradiant phase transition.
• To investigate the feasibility of quantum critical probes for parameter estimation, specifically frequency estimation.

Main Methods:

• Exploiting the superradiant phase transition of the quantum Rabi model.
• Designing and analyzing quantum metrological protocols for frequency estimation.

Main Results:

• Demonstrated that quantum critical probes can achieve enhanced time scaling of sensitivity.
• Showcased that this enhancement is possible despite the presence of critical slowing down.

Conclusions:

• Quantum critical optical probes offer a pathway to overcome limitations imposed by critical slowing down.
• These probes can achieve quantum-enhanced sensitivity scaling in frequency estimation protocols.