{ "id": "1301.7558", "version": "v1", "published": "2013-01-31T09:22:35.000Z", "updated": "2013-01-31T09:22:35.000Z", "title": "Optimality of a class of entanglement witnesses for $3\\otimes 3$ systems", "authors": [ "Xiaofei Qi", "Jinchuan Hou" ], "comment": "12 pages", "categories": [ "quant-ph" ], "abstract": "Let $\\Phi_{t,\\pi}: M_3({\\mathbb C}) \\rightarrow M_3({\\mathbb C})$ be a linear map defined by $\\Phi_{t,\\pi}(A)=(3-t)\\sum_{i=1}^3E_{ii}AE_{ii}+t\\sum_{i=1}^3E_{i,\\pi(i)}AE_{i,\\pi(i)}^\\dag-A$, where $0\\leq t\\leq 3$ and $\\pi$ is a permutation of $(1,2,3)$. We show that the Hermitian matrix $W_{\\Phi_{t,\\pi}}$ induced by $\\Phi_{t,\\pi}$ is an optimal entanglement witness if and only if $t=1$ and $\\pi$ is cyclic.", "revisions": [ { "version": "v1", "updated": "2013-01-31T09:22:35.000Z" } ], "analyses": { "subjects": [ "15A69", "15A86" ], "keywords": [ "entanglement witnesses", "optimality", "optimal entanglement witness", "hermitian matrix" ], "tags": [ "journal article" ], "publication": { "doi": "10.1007/s10773-013-1649-5", "journal": "International Journal of Theoretical Physics", "year": 2013, "month": "Oct", "volume": 52, "number": 10, "pages": 3474 }, "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013IJTP...52.3474Q" } } }