1997/03/31 by Pawel Horodecki · 3 citations
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1016/s0375-9601(97)00416-7
published as Phys.Lett. A232 (1997) 333 · It is improved and extended version of the former manuscript, in particular the theorem concerning finite decomposition of separable states has been included, 14 pages, RevTeX
arxiv created 1997/05/23 · arxiv updated 2009/12/01
It is shown that any separable state on Hilbert space \cal H=\cal H1⊗\cal H2, can be written as a convex combination of N pure product states with N≤ (dim\cal H)2. Then a new separability criterion for mixed states in terms of range of density matrix is obtained. It is used in construction of inseparable mixed states with positive partial transposition in the case of 3× 3 and 2× 4 systems. The states represent an entanglement which is hidden in a more subtle way than it has been known so far.