Joint measurements via quantum cloning

被引:24
作者
D'Ariano, GM
Macchiavello, C
Sacchi, MF
机构
[1] Theoret Quantum Opt Grp, Dipartimento Fis A Volta, I-27100 Pavia, Italy
[2] INFM, Unita Pavia, I-27100 Pavia, Italy
[3] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, Opt Sect, London SW7 2BW, England
关键词
quantum cloning; measurement of noncommuting observables;
D O I
10.1088/1464-4266/3/2/305
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
We explore the possibility of achieving the optimal joint measurement of noncommuting observables on a single quantum system by performing conventional measurements of commuting self-adjoint operators on the clones of the original quantum system. We consider the case of both finite-and infinite-dimensional Hilbert spaces. In the former we study the joint measurement of three orthogonal components of a spin 1/2; in the latter we consider the case of the joint measurement of any pair of noncommuting quadratures of one mode of the electromagnetic field. We show that universal covariant cloning is not ideal for joint measurements, and a suitable nonuniversal covariant cloning is needed.
引用
收藏
页码:44 / 50
页数:7
相关论文
共 26 条
[1]  
[Anonymous], 1993, Quantum Theory: Concepts and Methods, Fundamental Theories of Physics
[2]  
APPLEBY DM, 1999, QUANTPH9911021
[3]   ATOMIC COHERENT STATES IN QUANTUM OPTICS [J].
ARECCHI, FT ;
THOMAS, H ;
GILMORE, R ;
COURTENS, E .
PHYSICAL REVIEW A, 1972, 6 (06) :2211-&
[4]   ON SIMULTANEOUS MEASUREMENT OF A PAIR OF CONJUGATE OBSERVABLES [J].
ARTHURS, E ;
KELLY, JL .
BELL SYSTEM TECHNICAL JOURNAL, 1965, 44 (04) :725-+
[5]   QUANTUM CORRELATIONS - A GENERALIZED HEISENBERG UNCERTAINTY RELATION [J].
ARTHURS, E ;
GOODMAN, MS .
PHYSICAL REVIEW LETTERS, 1988, 60 (24) :2447-2449
[6]   Universal teleportation with a twist [J].
Braunstein, SL ;
D'Ariano, GM ;
Milburn, GJ ;
Sacchi, MF .
PHYSICAL REVIEW LETTERS, 2000, 84 (15) :3486-3489
[7]  
BRUB D, 2000, PHYS REV A, V6212, P302
[8]   Optimal universal and state-dependent quantum cloning [J].
Bruss, D ;
DiVincenzo, DP ;
Ekert, A ;
Fuchs, CA ;
Macchiavello, C ;
Smolin, JA .
PHYSICAL REVIEW A, 1998, 57 (04) :2368-2378
[9]   Optimal universal quantum cloning and state estimation [J].
Bruss, D ;
Ekert, A ;
Macchiavello, C .
PHYSICAL REVIEW LETTERS, 1998, 81 (12) :2598-2601
[10]   Quantum copying: Beyond the no-cloning theorem [J].
Buzek, V ;
Hillery, M .
PHYSICAL REVIEW A, 1996, 54 (03) :1844-1852