Entanglement witnesses of four-qubit tripartite separable quantum states  

作　　者：Miao Xu Wei-Feng Zhou Feng Chen Li-Zhen Jiang Xiao-Yu Chen 徐淼;周伟峰;陈峰;蒋丽珍;陈小余(College of Information and Electronic Engineering,Zhejiang Gongshang University,Hangzhou 310018,China;School of Information&Electrical Engineering,Zhejiang University City College,Hangzhou 310015,China)

机构地区：[1]College of Information and Electronic Engineering,Zhejiang Gongshang University,Hangzhou 310018,China [2]School of Information&Electrical Engineering,Zhejiang University City College,Hangzhou 310015,China

出　　处：《Communications in Theoretical Physics》2022年第3期20-26,共7页理论物理通讯（英文版）

基　　金：Supported by the National Natural Science Foundation of China(Grant No:61871347)。

摘　　要：A quantum entangled state is easily disturbed by noise and degenerates into a separable state.Compared to the entanglement with bipartite quantum systems,less progress has been made for the entanglement with multipartite quantum systems.For tripartite separability of a four-qubit system,we propose two entanglement witnesses,each of which corresponds to a necessary condition of tripartite separability.For the four-qubit GHZ state mixed with a W state and white noise,we prove that the necessary conditions of tripartite separability are also sufficient at W states side.

关 键 词：tripartite separability entanglement witness GHZ state W state 

分 类 号：O413[理学—理论物理]