Separability Criterion for Density Matrices.
نویسنده
چکیده
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 Bell inequality.
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عنوان ژورنال:
- Physical review letters
دوره 77 8 شماره
صفحات -
تاریخ انتشار 1996