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Satisfying the Einstein-Podolsky-Rosen criterion with massive particles
1Institut für Quantenoptik, Leibniz Universität Hannover, Welfengarten 1, D-30167 Hannover, Germany.
Nature Communications
|November 28, 2015
Summary
Scientists created a novel quantum state with ultracold atoms, demonstrating Einstein-Podolsky-Rosen (EPR) correlations in massive particles for the first time. This breakthrough advances quantum information and metrology research.
Area of Science:
- Quantum Physics
- Atomic Physics
- Quantum Information Science
Background:
- The Einstein-Podolsky-Rosen (EPR) paradox, proposed in 1935, questioned quantum mechanics' completeness using entangled particles with correlated properties.
- Continuous-variable EPR correlations have been demonstrated with photons but not yet with massive particles.
Purpose of the Study:
- To create and characterize an EPR-correlated two-mode squeezed state using massive particles in an ultracold atomic ensemble.
- To demonstrate the feasibility of generating strong quantum correlations with massive particles.
Main Methods:
- Generation of a two-mode squeezed state in an ultracold atomic ensemble.
- Characterization of the quantum state using an EPR entanglement parameter.
- Full tomographic reconstruction of the many-particle quantum state.
Main Results:
- Successful creation of an EPR-correlated two-mode squeezed state in an ultracold atomic ensemble.
- Measured EPR entanglement parameter of 0.18(3), significantly below the EPR criterion threshold of 1/4.
- Provided a complete tomographic reconstruction of the quantum state.
Conclusions:
- This work demonstrates the creation of EPR correlations with massive particles, a long-standing experimental challenge.
- The generated quantum state serves as a valuable resource for quantum nonlocality tests and continuous-variable quantum information applications, including metrology.
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