噪声中GHZ态和W态混合态的相干鲁棒性研究  

Robustness of coherence of GHZ and W mixed states in white noise

作　　者：周伟峰 徐淼 陈小余 ZHOU Weifeng;XU Miao;CHEN Xiaoyu(College of Information and Electronic Engineering,Zhejiang Gongshang University,Hangzhou Zhejiang 310018,China;School of Information and Electrical Engineering,Zhejiang University City College,Hangzhou Zhejiang 310015,China)

机构地区：[1]浙江工商大学信息与电子工程学院,浙江杭州310018 [2]浙江大学城市学院信息与电气工程学院,浙江杭州310015

出　　处：《杭州电子科技大学学报（自然科学版）》2022年第6期15-19,共5页Journal of Hangzhou Dianzi University：Natural Sciences

基　　金：国家自然科学基金资助项目(61871347)。

摘　　要：研究量子混合态的相干鲁棒性问题。首先,引入量子态的相干鲁棒性理论,提出可测量的最优相干见证者模型;然后,以格林伯格-霍恩-塞林格(Greenberger-Horne-Zeilinger, GHZ)态和W态在白噪声中混合态的密度矩阵为基础,运用泡利矩阵对混合态进行重构,得到一组特性系数和相干见证算符;最后,根据最优相干见证者实现对混合态相干鲁棒性的计算。研究结果表明,任意N量子比特噪声GHZ-W态(噪声中GHZ态和W态混合态)的相干鲁棒性和l-范数相干度量结果一致。This paper is to study the robustness of coherence of quantum mixed states. Firstly, according to the robustness of coherence theory of quantum states, we propose a measurable optimal coherence witness model. Secondly, based on the density matrix of the mixed state of a Greenberger-Horne-Zeilinger(GHZ) state and a W state in white noise, we use the Pauli matrices to reconstruct the mixed state to obtain a set of characteristic cofficients and coherence witness operators. Finally, the robustness of coherence computation for the mixed state is achieved according to the optimal coherence witness. The robustness of coherence of arbitrary N-qubit GHZ and W mixed states in white noise(noisy GHZ-W states) is shown to be equivalent to the l-norm coherence measure.

关 键 词：相干鲁棒性 最优相干见证者 GHZ态 W态 

分 类 号：TN918.1[电子电信—通信与信息系统]