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Updated: Jul 13, 2025
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
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Acoustic frequency atomic spin oscillator in the quantum regime
Jun Jia1, Valeriy Novikov1,2, Tulio Brito Brasil1
1Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
Nature Communications
|October 12, 2023
Summary
This study demonstrates quantum behavior in macroscopic atomic spin oscillators at acoustic frequencies. Researchers observed quantum noise reduction and entanglement-enhanced sensing, crucial for magnetometry and gravitational wave detection.
Area of Science:
- Quantum physics
- Atomic physics
- Optics
Background:
- Quantum noise reduction and entanglement-enhanced sensing are critical for applications like magnetometry and gravitational wave detection.
- Operating in the acoustic frequency range presents significant challenges for these quantum technologies.
Purpose of the Study:
- To experimentally demonstrate quantum behavior in a macroscopic atomic spin oscillator within the acoustic frequency range.
- To identify quantum noise sources in spin oscillators at near-DC frequencies and propose mitigation strategies.
Main Methods:
- Utilizing a macroscopic atomic spin oscillator.
- Observing quantum back-action of spin measurement.
- Employing ponderomotive squeezing of light.
- Investigating virtual spring softening effects.
Main Results:
- Quantum behavior was demonstrated at oscillation frequencies as low as the sub-kHz range.
- Ponderomotive squeezing of light and virtual spring softening were experimentally observed.
- Characteristic quantum noise sources in near-DC spin oscillators were identified.
Conclusions:
- Macroscopic atomic spin oscillators exhibit quantum behavior in the acoustic frequency range.
- The findings offer pathways for quantum noise reduction and enhanced sensing in sensitive scientific instruments.
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