Constructing optimal entanglement witnesses

Journal Article · Tue Dec 15 00:00:00 EST 2009 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.80.062314· OSTI ID:21352314

Chruscinski, Dariusz; Pytel, Justyna; Sarbicki, Gniewomir ^[1]

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1. Institute of Physics, Nicolaus Copernicus University, GrudziaPdzka 5/7, 87-100 Torun (Poland)

We provide a class of indecomposable entanglement witnesses. In 4x4 case, it reproduces the well-known Breuer-Hall witness. We prove that these witnesses are optimal and atomic, i.e., they are able to detect the 'weakest' quantum entanglement encoded into states with positive partial transposition. Equivalently, we provide a construction of indecomposable atomic maps in the algebra of 2kx2k complex matrices. It is shown that their structural physical approximations give rise to entanglement breaking channels. This result supports recent conjecture by Korbicz et al. [Phys. Rev. A 78, 062105 (2008)].

• OSTI ID: 21352314
• Journal Information: Physical Review. A, Vol. 80, Issue 6; Other Information: DOI: 10.1103/PhysRevA.80.062314; (c) 2009 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALGEBRA
APPROXIMATIONS
MAPS
MATRICES
QUANTUM ENTANGLEMENT
CALCULATION METHODS
MATHEMATICS