How quantum is a quantum ensemble?

doi:10.1007/s11128-010-0162-5

CSpace > 应用数学研究所

	How quantum is a quantum ensemble?
	Luo, Shunlong1 ; Li, Nan1 ; Sun, Wei 2
	2010-12-01
发表期刊	QUANTUM INFORMATION PROCESSING
ISSN	1570-0755
卷号	9 期号:6 页码:711-726
摘要	In the Hilbert space operator formalism of quantum mechanics, a single quantum state, which is represented by a density operator, can be regarded as classical in the sense that it can always be diagonalized. However, a quantum ensemble, which is represented by a family of quantum states together with a probability distribution specifying the probability of the occurrence of each state, cannot be diagonalized simultaneously in generic cases, and possesses intrinsic quantum features as long as the involved quantum states are not commutative. The natural question arises as how to quantify its quantumness. By virtue of a canonical correspondence between quantum ensembles and classical-quantum bipartite states, we propose an intuitive entropic quantity which captures certain quantum features of quantum ensembles, and compare it with that defined as the gap between the Holevo quantity and the accessible information. Implications for quantum cryptography and relations to quantum channel capacities are indicated. Some illustrative examples are worked out.
关键词	Quantum ensemble Von Neumann measurement Quantum correlations Holevo quantity
DOI	10.1007/s11128-010-0162-5
语种	英语
资助项目	NSFC[10771208] ; Key Lab of Random Complex Structures and Data Science, CAS[2008DP173182] ; NSERC[311945-2008]
WOS研究方向	Physics
WOS类目	Physics, Multidisciplinary ; Physics, Mathematical
WOS记录号	WOS:000283943100005
出版者	SPRINGER
引用统计
文献类型	期刊论文
条目标识符	http://ir.amss.ac.cn/handle/2S8OKBNM/10573
专题	应用数学研究所
通讯作者	Luo, Shunlong
作者单位	1.Chinese Acad Sci, Acad Math & Syst Sci, Beijing 100190, Peoples R China 2.Concordia Univ, Dept Math & Stat, Montreal, PQ H3G 1M8, Canada
推荐引用方式 GB/T 7714	Luo, Shunlong,Li, Nan,Sun, Wei. How quantum is a quantum ensemble?[J]. QUANTUM INFORMATION PROCESSING,2010,9(6):711-726.
APA	Luo, Shunlong,Li, Nan,&Sun, Wei.(2010).How quantum is a quantum ensemble?.QUANTUM INFORMATION PROCESSING,9(6),711-726.
MLA	Luo, Shunlong,et al."How quantum is a quantum ensemble?".QUANTUM INFORMATION PROCESSING 9.6(2010):711-726.