Efficient quantum state tomography

被引：486

作者：

Cramer, Marcus ^{[1
]}

Plenio, Martin B. ^{[1
]}

Flammia, Steven T. ^{[2
]}

Somma, Rolando ^{[2
]}

Gross, David ^{[3
]}

Bartlett, Stephen D. ^{[4
]}

Landon-Cardinal, Olivier ^{[5
]}

Poulin, David ^{[5
]}

Liu, Yi-Kai ^{[6
]}

机构：

[1] Univ Ulm, Inst Theoret Phys, D-89069 Ulm, Germany

[2] Perimeter Inst Theoret Phys, Waterloo, ON N2L 2Y5, Canada

[3] Leibniz Univ Hannover, Inst Theoret Phys, D-30167 Hannover, Germany

[4] Univ Sydney, Sch Phys, Sydney, NSW 2006, Australia

[5] Univ Sherbrooke, Dept Phys, Sherbrooke, PQ J1K 2R1, Canada

[6] Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA

来源：

NATURE COMMUNICATIONS | 2010年 / 1卷

基金：

澳大利亚研究理事会; 美国国家科学基金会; 加拿大自然科学与工程研究理事会;

关键词：

DENSITY-MATRIX RENORMALIZATION; ENTANGLEMENT;

D O I：

10.1038/ncomms1147

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Quantum state tomography-deducing quantum states from measured data-is the gold standard for verification and benchmarking of quantum devices. It has been realized in systems with few components, but for larger systems it becomes unfeasible because the number of measurements and the amount of computation required to process them grows exponentially in the system size. Here, we present two tomography schemes that scale much more favourably than direct tomography with system size. One of them requires unitary operations on a constant number of subsystems, whereas the other requires only local measurements together with more elaborate post-processing. Both rely only on a linear number of experimental operations and post-processing that is polynomial in the system size. These schemes can be applied to a wide range of quantum states, in particular those that are well approximated by matrix product states. The accuracy of the reconstructed states can be rigorously certified without any a priori assumptions.

引用

页数：7

共 39 条

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