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Activation of Nonlocality in Bound Entanglement
Lucas Tendick1, Hermann Kampermann1, Dagmar Bruß1
1Institute for Theoretical Physics III, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf, Germany.
Physical Review Letters
|February 22, 2020
Summary
Bound entangled states can exhibit hidden nonlocality, a quantum phenomenon activated by local filters. This study demonstrates that genuine hidden nonlocality does not necessitate entanglement distillability.
Area of Science:
- Quantum Information Theory
- Quantum Foundations
Background:
- Nonlocality is a key feature of quantum mechanics, distinguishing it from classical physics.
- Hidden nonlocality refers to nonlocality that can be revealed in quantum states using local operations.
- Bound entanglement is a type of entanglement that cannot be distilled into pure entanglement by local operations and classical communication.
Purpose of the Study:
- To investigate the relationship between entanglement and nonlocality in the context of hidden nonlocality.
- To demonstrate that bound entangled states can exhibit hidden nonlocality.
- To explore the implications of hidden nonlocality for entanglement distillability.
Main Methods:
- Construction of a fully biseparable three-qubit bound entangled state.
- Analysis of the state using a local hidden-variable model for general measurements.
- Application of local filters to activate nonlocality.
Main Results:
- A novel bound entangled state was shown to admit a local model for general measurements.
- The local model for this state was demonstrated to break down upon application of specific local filters.
- This represents the first experimental evidence of hidden nonlocality activation in bound entangled states.
Conclusions:
- Bound entangled states can possess hidden nonlocality, which can be activated by local filters.
- Genuine hidden nonlocality does not imply that an entangled state is distillable.
- This finding advances our understanding of the interplay between entanglement, nonlocality, and information processing in quantum systems.
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