Universität zu Köln

Hou, Zhibo, Zhu, Huangjun, Xiang, Guo-Yong, Li, Chuan-Feng and Guo, Guang-Can (2016). Achieving quantum precision limit in adaptive qubit state tomography. LONDON: NATURE PUBLISHING GROUP. ISSN 2056-6387

Full text not available from this repository.

Abstract

The precision limit in quantum state tomography is of great interest not only to practical applications but also to foundational studies. However, little is known about this subject in the multiparameter setting even theoretically due to the subtle information trade-off among incompatible observables. In the case of a qubit, the theoretic precision limit was determined by Hayashi as well as Gill and Massar, but attaining the precision limit in experiments has remained a challenging task. Here we report the first experiment that achieves this precision limit in adaptive quantum state tomography on optical polarisation qubits. The two-step adaptive strategy used in our experiment is very easy to implement in practice. Yet it is surprisingly powerful in optimising most figures of merit of practical interest. Our study may have significant implications for multiparameter quantum estimation problems, such as quantum metrology. Meanwhile, it may promote our understanding about the complementarity principle and uncertainty relations from the information theoretic perspective.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Hou, Zhibo UNSPECIFIED UNSPECIFIED UNSPECIFIED Zhu, Huangjun UNSPECIFIED UNSPECIFIED UNSPECIFIED Xiang, Guo-Yong UNSPECIFIED UNSPECIFIED UNSPECIFIED Li, Chuan-Feng UNSPECIFIED UNSPECIFIED UNSPECIFIED Guo, Guang-Can UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-284327
DOI:	10.1038/npjqi.2016.1
Volume:	2
Date:	2016
Publisher:	NATURE PUBLISHING GROUP
Place of Publication:	LONDON
ISSN:	2056-6387
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language INFORMATION Multiple languages Quantum Science & Technology; Physics, Applied; Physics, Atomic, Molecular & Chemical; Physics, Condensed Matter Multiple languages
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/28432