{ "id": "0709.0027", "version": "v2", "published": "2007-09-01T01:56:51.000Z", "updated": "2008-06-10T15:20:00.000Z", "title": "Robustness of entangled states that are positive under partial transposition", "authors": [ "Somshubhro Bandyopadhyay", "Sibasish Ghosh", "Vwani Roychowdhury" ], "comment": "Published version", "journal": "Phys. Rev. A 77, 032318 (2008)", "doi": "10.1103/PhysRevA.77.032318", "categories": [ "quant-ph" ], "abstract": "We study robustness of bipartite entangled states that are positive under partial transposition (PPT). It is shown that almost all PPT entangled states are unconditionally robust, in the sense, both inseparability and positivity are preserved under sufficiently small perturbations in its immediate neighborhood. Such unconditionally robust PPT entangled states lie inside an open PPT entangled ball. We construct examples of such balls whose radii are shown to be finite and can be explicitly calculated. This provides a lower bound on the volume of all PPT entangled states. Multipartite generalization of our constructions are also outlined.", "revisions": [ { "version": "v2", "updated": "2008-06-10T15:20:00.000Z" } ], "analyses": { "subjects": [ "03.67.Mn", "03.65.Ud" ], "keywords": [ "partial transposition", "robustness", "ppt entangled states lie inside", "robust ppt entangled states lie", "unconditionally robust ppt entangled states" ], "tags": [ "journal article" ], "publication": { "publisher": "APS", "journal": "Physical Review A", "year": 2008, "month": "Mar", "volume": 77, "number": 3, "pages": "032318" }, "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008PhRvA..77c2318B" } } }