A note on generalized concurrences and entanglement detection
نویسنده
چکیده
Consider a bipartite quantum system consisting of two subsystems A and B, of dimensions nA and nB , respectively. The overall system has dimension n := nAnB. The state of the total system is represented by an Hermitian n×nmatrix ρ, called the density matrix, which is positive semi-definite and has trace equal to one. Special types of density matrices are product matrices, i.e., matrices ρprod of the form ρprod := ρA ⊗ ρB , where ρA and ρB are themselves density matrices (i.e., Hermitian, positive semi-definite, with trace 1) of dimensions nA × nA and nB × nB, respectively. A density matrix is called separable if it is the finite convex combination of product states, that is,
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