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Multipartite bound entangled states that violate Bell's inequality
1Institut für Theoretische Physik, Universität Innsbruck, A-6020 Innsbruck, Austria.
Physical Review Letters
|December 12, 2001
Summary
Bound entangled states, which are nondistillable, can violate Bell inequalities. This finding shows Bell inequality violation doesn't guarantee distillability and some bound entangled states defy local hidden variable models.
Area of Science:
- Quantum Information Theory
- Quantum Foundations
Background:
- Multipartite quantum states are crucial for quantum information processing.
- Distillability and Bell's inequality violation are key concepts in characterizing quantum entanglement.
- Bound entangled states are a peculiar class of entangled states that cannot be distilled into pure entanglement.
Purpose of the Study:
- To investigate the relationship between the distillability of multipartite quantum states and their ability to violate Bell's inequality.
- To determine if Bell's inequality violation is a sufficient condition for distillability in multipartite systems.
- To explore the implications for local hidden variable models in describing bound entangled states.
Main Methods:
- Theoretical analysis of multipartite quantum states.
- Construction of specific examples of bound entangled states.
- Application of Bell's inequality tests to these states.
Main Results:
- Demonstration of the existence of multipartite bound entangled states that violate a multipartite Bell inequality.
- Proof that Bell's inequality violation is not a sufficient condition for distillability.
- Identification of bound entangled states that cannot be explained by local hidden variable models.
Conclusions:
- Bell's inequality violation alone is insufficient to guarantee the distillability of multipartite quantum states.
- Certain bound entangled states exhibit non-classical correlations that cannot be captured by local hidden variable theories.
- This research deepens our understanding of the nature of entanglement and its non-classical properties.
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