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09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Minimum detection efficiency for a loophole-free atom-photon bell experiment.
Adán Cabello1, Jan-Ake Larsson
1Departamento de Física Aplicada II, Universidad de Sevilla, E-41012 Sevilla, Spain. adan@us.es
Physical Review Letters
|August 7, 2007
Summary
Achieving loophole-free Bell experiments requires high photodetection efficiency. Atom-photon experiments can lower this threshold to 0.50, assuming perfect atom detection.
Area of Science:
- Quantum mechanics
- Quantum information science
- Experimental physics
Background:
- Bell experiments test the foundations of quantum mechanics.
- Local hidden-variable models are challenged by Bell's theorem.
- Previous experiments require high photodetection efficiency (>0.67) to rule out local hidden-variable models.
Purpose of the Study:
- To investigate the photodetection efficiency requirements for loophole-free atom-photon Bell experiments.
- To determine if atom-photon systems can reduce the necessary detection efficiency compared to traditional Bell tests.
Main Methods:
- Analysis of atom-photon Bell experiments.
- Application of the Clauser-Horne inequality.
- Consideration of a two-photon nonmaximally entangled state.
- Theoretical modeling assuming perfect atom detection efficiency.
Main Results:
- A photodetection efficiency exceeding 0.50 is sufficient for loophole-free atom-photon Bell experiments.
- This represents a significant reduction in the required efficiency compared to previous Bell experiments.
- The assumption of perfect atom detection is crucial for this lower threshold.
Conclusions:
- Atom-photon Bell experiments offer a more feasible route to closing the photodetection loophole.
- These findings advance the experimental verification of quantum mechanics and the exploration of quantum information processing.
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