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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Distinguishing separable and entangled states
A C Doherty1, Pablo A Parrilo, Federico M Spedalieri
1Institute for Quantum Information, California Institute of Technology, Pasadena, CA 91125, USA.
Physical Review Letters
|May 15, 2002
Summary
We developed new operational criteria to identify entangled quantum states, improving upon the Peres-Horodecki positive partial transpose (PPT) criterion. These methods utilize semidefinite programming for practical application to complex quantum systems.
Area of Science:
- Quantum Information Science
- Quantum Computing
- Quantum Physics
Background:
- Distinguishing entangled from separable quantum states is fundamental in quantum information.
- Existing criteria, like the Peres-Horodecki positive partial transpose (PPT), have limitations.
- Entanglement witnesses are crucial for detecting entanglement.
Purpose of the Study:
- To design novel operational criteria for detecting entangled quantum states.
- To develop criteria that are strictly stronger than the PPT criterion.
- To provide explicit constructions for entanglement witnesses.
Main Methods:
- Utilizing semidefinite programming, a powerful convex optimization technique.
- Developing families of operational criteria for entanglement detection.
- Applying new criteria to low-dimensional quantum states where PPT fails.
Main Results:
- Introduced new, stronger criteria for distinguishing entangled from separable states.
- Demonstrated the tractability of these criteria using computational methods.
- Successfully applied the criteria to challenging quantum states from existing literature.
Conclusions:
- The new criteria offer enhanced capabilities for entanglement detection.
- Semidefinite programming provides an efficient framework for these advanced tests.
- The work yields practical tools, including explicit entanglement witnesses, for quantum state characterization.
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