{ "id": "0908.0119", "version": "v1", "published": "2009-08-03T16:22:40.000Z", "updated": "2009-08-03T16:22:40.000Z", "title": "The Perfect Distinguishability of Quantum Operations", "authors": [ "Runyao Duan", "Yuan Feng", "Mingsheng Ying" ], "comment": "6.25 pages (Revtex 4), a preliminary version. Comments are welcome", "doi": "10.1103/PhysRevLett.103.210501", "categories": [ "quant-ph" ], "abstract": "We provide a feasible necessary and sufficient condition for when an unknown quantum operation (quantum device) secretely selected from a set of known quantum operations can be identified perfectly within a finite number of queries, and thus complete the characterization of the perfect distinguishability of quantum operations. We further design an optimal protocol which can achieve the perfect discrimination between two quantum operations by a minimal number of queries. Interestingly, employing the techniques from the theory of $q$-numerical range we find that an optimal perfect discrimination between two isometries is always achievable without using auxiliary systems or entanglement.", "revisions": [ { "version": "v1", "updated": "2009-08-03T16:22:40.000Z" } ], "analyses": { "subjects": [ "03.67.Ac", "03.65.Ta", "03.67.Hk" ], "keywords": [ "perfect distinguishability", "unknown quantum operation", "optimal perfect discrimination", "finite number", "auxiliary systems" ], "tags": [ "journal article" ], "publication": { "publisher": "APS", "journal": "Physical Review Letters", "year": 2009, "month": "Nov", "volume": 103, "number": 21, "pages": 210501 }, "note": { "typesetting": "RevTeX", "pages": 25, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009PhRvL.103u0501D" } } }