摘要
Einstein-Podolsky-Rosen(EPR)导引是一种介于量子纠缠和贝尔非定域性之间的量子关联,它存在于不具有定域隐态模型描述的纠缠态中。定域隐态模型是指,对复合系统子系统的测量输出,包括测量结果和其余部分塌缩后的态,可以利用经典随机变量和制备单体态来模拟。构造一族态最优的定域隐态模型,等价于给出该族态EPR导引的充要判据。然而,定域隐态模型的构造是个相当困难的问题,现有的大部分结果都可以看成是Werner在1989年所给模型的在不同意义上的变形。本文首先介绍EPR导引及定域隐态模型的定义和一些普遍性质,而后重点讨论正交测量下两量子比特系统的定域隐态模型,其中尤其值得注意的是T态与Werner态在定域隐态模型问题上的对应关系。
Einstein-Podolsky-Rosen(EPR)steering is a form of quantum correlation in composed quantum systems,which intermediates between entanglement and Bell nonlocality.An entangled state,shared by Alice to Bob,is said to be EPR steerable from Alice to Bob,when Alice’s unnormalized post-measured states cannot be described by a local hidden state(LHS)model.A LHS strategy can be designed based on the LHS model to simulate the results of Alice’s measurements without any entangled state.The optimal LHS model for a family of states is equivalent to a necessary and sufficient criterion for the EPR steering.However,the construction of LHS models is an extremely difficult problem.Most of the existing models can be interpreted as variants of Werner’s original construction in 1989.This paper first gives a brief review of the concepts of EPR steering and LHS model and then focuses on the introduction of some LHS models under the context of two-qubit system and projective measurements.A noteworthy point is the mapping from the problem of LHS model for T-states to the Werner state.
作者
张媛媛
张宵玉
任昌亮
张福林
ZHANG Yuan-yuan;ZHANG Xiao-yu;REN Chang-liang;ZHANG Fu-lin(Department of Physics,School of Science,Tianjin University,Tianjin300072,China;Department of Physics,Chinese Academy of Sciences,Beijing101400,China;Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,Chongqing400714,China)
出处
《量子光学学报》
北大核心
2019年第4期363-371,共9页
Journal of Quantum Optics
基金
国家自然科学基金(11675119,11575125,11105097).
