摘要
研究了无限维量子系统上保真度的问题.首先,利用量子保真度无限维版本的Uhlmann定理,获得了在无限维量子系统上关于量子保真度的强凹性、联合凹性和凹性等性质.其次,给出纠缠保真度与其量子态纯化选择无关的一个初等证明.最后,讨论了纠缠保真度与系综平均保真度之间的关系,得出系综平均保真度是纠缠保真度的一个上界.
The fidelity in the infinite-dimensional quantum systems was investigated. Firstly, based on the infinite-dimensional version of Uhlmann＇s theorem of fidelity, the properties of strong concavity, joint concavity and concavity of quantum fidelity in the infinite-dimensional quantum systems were obtained. Next, an elementary proof that the entanglement fidelity was independent on the choice of purifi- cation of the quantum state was given. Finally, the relationship between entanglement fidelity and ensemble average fidelity was discussed, it is concluded that ensemble average fidelity is an upper bound of entanglement fidelity.
出处
《中北大学学报（自然科学版）》
CAS
2018年第1期21-24,共4页
Journal of North University of China(Natural Science Edition)
基金
山西省基础研究计划资助项目(2015021009)
关键词
无限维量子系统
保真度
纠缠保真度
系综平均保真度
infinite-dimensional quantum systems
fidelity
entanglement fidelity
ensemble average fidelity
