Relations between entanglement witnesses and Bell inequalities -: art. no. 012321

被引:92
作者
Hyllus, P [1 ]
Gühne, O
Bruss, D
Lewenstein, M
机构
[1] Leibniz Univ Hannover, Inst Theoret Phys, D-30167 Hannover, Germany
[2] Austrian Acad Sci, Inst Quantenopt & Quanteninformat, A-6020 Innsbruck, Austria
[3] Univ Dusseldorf, Inst Theoret Phys 3, D-40225 Dusseldorf, Germany
[4] Inst Ciencies Foton, ICFO, Barcelona 08034, Spain
关键词
D O I
10.1103/PhysRevA.72.012321
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
Bell inequalities, considered within quantum mechanics, can be regarded as nonoptimal witness operators. We discuss the relationship between such Bell witnesses and general entanglement witnesses in detail for the Bell inequality derived by Clauser, Horne, Shimony, and Holt (CHSH) [Phys. Rev. Lett. 23, 880 (1969)]. We derive bounds on how much an optimal witness has to be shifted by adding the identity operator to make it positive on all states admitting a local hidden variable model. In the opposite direction, we obtain tight bounds for the maximal proportion of the identity operator that can be subtracted from such a CHSH witness, while preserving the witness properties. Finally, we investigate the structure of CHSH witnesses directly by relating their diagonalized form to optimal witnesses of two different classes.
引用
收藏
页数:7
相关论文
共 33 条
[1]   Quantum nonlocality in two three-level systems -: art. no. 052325 [J].
Acín, A ;
Durt, T ;
Gisin, N ;
Latorre, JI .
PHYSICAL REVIEW A, 2002, 65 (05) :523251-523258
[2]   BELL INEQUALITIES WITH A MAGNITUDE OF VIOLATION THAT GROWS EXPONENTIALLY WITH THE NUMBER OF PARTICLES [J].
ARDEHALI, M .
PHYSICAL REVIEW A, 1992, 46 (09) :5375-5378
[3]   Detection of entanglement with polarized photons: Experimental realization of an entanglement witness [J].
Barbieri, M ;
De Martini, F ;
Di Nepi, G ;
Mataloni, P ;
D'Ariano, GM ;
Macchiavello, C .
PHYSICAL REVIEW LETTERS, 2003, 91 (22)
[4]   Nonlocal correlations as an information-theoretic resource [J].
Barrett, J ;
Linden, N ;
Massar, S ;
Pironio, S ;
Popescu, S ;
Roberts, D .
PHYSICAL REVIEW A, 2005, 71 (02)
[5]   Nonsequential positive-operator-valued measurements on entangled mixed states do not always violate a Bell inequality [J].
Barrett, J .
PHYSICAL REVIEW A, 2002, 65 (04) :4
[6]   THE INTERFERENCE OF LIGHT AND THE BELL THEOREM [J].
BELINSKII, AV ;
KLYSHKO, DN .
USPEKHI FIZICHESKIKH NAUK, 1993, 163 (08) :1-45
[7]  
Bell JS., 1964, PHYS PHYS FIZIKA, V1, P195, DOI [10.1103/Physics-PhysiqueFizika.1.195, 10.1103/PhysicsPhysiqueFizika.1.195, DOI 10.1103/PHYSICSPHYSIQUEFIZIKA.1.195]
[8]   Experimental detection of multipartite entanglement using witness operators -: art. no. 087902 [J].
Bourennane, M ;
Eibl, M ;
Kurtsiefer, C ;
Gaertner, S ;
Weinfurter, H ;
Gühne, O ;
Hyllus, P ;
Bruss, D ;
Lewenstein, M ;
Sanpera, A .
PHYSICAL REVIEW LETTERS, 2004, 92 (08)
[9]   Entanglement and non-locality are different resources [J].
Brunner, N ;
Gisin, N ;
Scarani, V .
NEW JOURNAL OF PHYSICS, 2005, 7
[10]  
CERF NJ, 2005, PHYS REV LETT, V94