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Event-Ready Bell Test Using Entangled Atoms Simultaneously Closing Detection and Locality Loopholes
Wenjamin Rosenfeld1,2, Daniel Burchardt1, Robert Garthoff1
1Fakultät für Physik, Ludwig-Maximilians-Universität München, D-80799 München, Germany.
Physical Review Letters
|July 22, 2017
Summary
This experiment demonstrates a violation of Bell's inequality, refuting local realism. It used entangled atoms and efficient measurements to close loopholes in quantum physics tests.
Area of Science:
- Quantum Physics
- Foundations of Quantum Mechanics
- Experimental Quantum Information
Background:
- Bell's inequality tests challenge local-realism, a classical view of nature.
- Previous tests were hampered by loopholes in detection efficiency and spacelike separation.
- Simultaneously closing these loopholes has been a recent experimental challenge.
Purpose of the Study:
- To perform a statistically significant, event-ready Bell test.
- To close the detection efficiency and spacelike separation loopholes simultaneously.
- To experimentally refute the hypothesis of local realism.
Main Methods:
- Utilized heralded entanglement of atoms separated by 398 meters.
- Employed fast and efficient measurements of atomic spin states.
- Combined these techniques to create an event-ready Bell test.
Main Results:
- Achieved a violation of Bell's inequality with S=2.221±0.033.
- This value significantly exceeds the maximum of 2 predicted by local hidden variable models.
- Refuted local realism with a high statistical significance (P<2.57×10^{-9}).
Conclusions:
- The experiment provides strong evidence against local realism.
- Demonstrates the feasibility of closing critical loopholes in Bell tests.
- Advances our understanding of the fundamental nature of quantum reality.
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