{ "id": "1306.0349", "version": "v2", "published": "2013-06-03T11:00:15.000Z", "updated": "2013-09-02T14:17:13.000Z", "title": "Decomposition of any quantum measurement into extremals", "authors": [ "G. Sentís", "B. Gendra", "S. D. Bartlett", "A. C. Doherty" ], "comment": "10 pages", "journal": "J. Phys. A: Math. Theor. 46 (2013) 375302", "doi": "10.1088/1751-8113/46/37/375302", "categories": [ "quant-ph" ], "abstract": "We design an efficient and constructive algorithm to decompose any generalized quantum measurement into a convex combination of extremal measurements. We show that if one allows for a classical post-processing step only extremal rank-1 POVMs are needed. For a measurement with $N$ elements on a $d$-dimensional space, our algorithm will decompose it into at most $(N-1)d+1$ extremals, whereas the best previously known upper bound scaled as $d^2$. Since the decomposition is not unique, we show how to tailor our algorithm to provide particular types of decompositions that exhibit some desired property.", "revisions": [ { "version": "v2", "updated": "2013-09-02T14:17:13.000Z" } ], "analyses": { "keywords": [ "decomposition", "upper bound", "extremal measurements", "generalized quantum measurement", "dimensional space" ], "tags": [ "journal article" ], "publication": { "journal": "Journal of Physics A Mathematical General", "year": 2013, "month": "Sep", "volume": 46, "number": 37, "pages": 375302 }, "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013JPhA...46K5302S" } } }