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Adaptive cold-atom magnetometry mitigating the trade-off between sensitivity and dynamic range
Zhu Ma1,2, Chengyin Han1,3, Zhi Tan1
1Institute of Quantum Precision Measurement, State Key Laboratory of Radio Frequency Heterogeneous Integration, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China.
Science Advances
|February 28, 2025
Summary
This study demonstrates adaptive cold-atom magnetometry, achieving superior sensitivity and dynamic range for magnetic field detection. The quantum sensor surpasses the standard quantum limit, paving the way for advanced quantum sensing technologies.
Area of Science:
- Quantum Sensing
- Atomic Physics
- Metrology
Background:
- Cold-atom magnetometers offer high sensitivity and spatial resolution.
- Improving sensitivity and dynamic range simultaneously remains a key challenge for quantum sensors.
Purpose of the Study:
- To experimentally demonstrate an adaptive entanglement-free cold-atom magnetometry technique.
- To achieve superior sensitivity and high dynamic range in magnetic field measurements.
Main Methods:
- Utilized a tailored adaptive Bayesian quantum estimation algorithm for Ramsey interferometry with coherent population trapping (CPT).
- Implemented a sequence of correlated CPT-Ramsey interferometry.
- Employed adaptive measurement strategies leveraging real-time data.
Main Results:
- Achieved a sensitivity of 6.8 ± 0.1 picotesla per square root of hertz over a 145.6 nanotesla range.
- Demonstrated sensitivity surpassing the standard quantum limit with respect to total interrogation time.
- Exceeded conventional frequentist protocols by 3.3 ± 0.1 decibels.
Conclusions:
- The developed adaptive cold-atom magnetometry provides a significant advancement in quantum sensing.
- This technique enables high-precision DC magnetic field detection with an enhanced dynamic range.
- Opens new possibilities for next-generation adaptive quantum sensors by utilizing real-time measurement history.
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