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Transmission estimation at the quantum Cramér-Rao bound with macroscopic quantum light
Timothy S Woodworth1,2, Carla Hermann-Avigliano3,4, Kam Wai Clifford Chan5
1Homer L. Dodge Department of Physics and Astronomy, The University of Oklahoma, Norman, Oklahoma 73019 USA.
EPJ Quantum Technology
|December 27, 2022
Summary
Quantum metrology enhances sensing precision using quantum resources. Experiments achieved the quantum limit for transmission estimation, reducing variance by 62% with bright two-mode squeezed states.
Area of Science:
- Quantum physics
- Metrology
- Quantum optics
Background:
- Quantum metrology aims to surpass classical sensing limits using quantum phenomena.
- The quantum Cramér-Rao bound sets the theoretical precision limit for parameter estimation.
- Practical implementation requires experimental methods to reach this quantum bound.
Purpose of the Study:
- To experimentally saturate the quantum Cramér-Rao bound for transmission estimation.
- To investigate the use of continuous wave bright two-mode squeezed states for enhanced sensing.
- To account for experimental imperfections in quantum state generation.
Main Methods:
- Probing a system with a bright two-mode squeezed state.
- Performing transmission estimation experiments.
- Extending theoretical models to include measured properties of the generated quantum state.
Main Results:
- Experimental saturation of the quantum Cramér-Rao bound across a range of transmissions.
- A 62% reduction in variance for transmission estimation at 84% transmission.
- Demonstrated precision using a bright two-mode squeezed state with -8 dB squeezing.
Conclusions:
- The study experimentally validates the use of quantum states for surpassing classical sensing limits.
- Achieved precision in transmission estimation has broad implications for various sensing applications.
- This work paves the way for practical quantum-enhanced measurement technologies.
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