Operational criterion and constructive checks for the separability of low-rank density matrices
نویسندگان
چکیده
منابع مشابه
Separability Criterion for Density Matrices.
A quantum system consisting of two subsystems is separable if its density matrix can be written as ρ = ∑ A wA ρ ′ A ⊗ ρ ′′ A, where ρ ′ A and ρ ′′ A are density matrices for the two subsytems. In this Letter, it is shown that a necessary condition for separability is that a matrix, obtained by partial transposition of ρ, has only non-negative eigenvalues. This criterion is stronger than the Bel...
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ژورنال
عنوان ژورنال: Physical Review A
سال: 2000
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.62.032310