空间纠缠协助下对低纠缠GHZ态的确定性纠缠纯化  

Deterministic entanglement purification for decohered GHZ state assisted by spatial entanglement

作　　者：朱孟正[1] 苏梦远 公丕锋[1] 张金锋[1] ZHU Mengzheng;SU Mengyuan;GONG Pifeng;ZHANG Jinfeng(School of Physics&Electronic Information,Huaibei Normal University,Huaibei 235000,China)

机构地区：[1]淮北师范大学物理与电子信息学院,安徽淮北235000

出　　处：《量子电子学报》2023年第6期943-951,共9页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金(51973078);安徽省自然科学基金(1808085MA08)。

摘　　要：基于偏振分束器和半波片线性光学元件,把在偏振自由度中出现的比特翻转和相位翻转错误转移到空间自由度中,从而实现针对极化低纠缠GHZ态的确定性纠缠纯化。利用线性光学和超纠缠的方法,该确定性纠缠纯化方案实施过程中无需知晓待纯化的低纠缠GHZ态的任何参数,无需将偏振自由度中相位翻转错误转化成比特翻转再进行纯化,也无需引入非线性效应,仅需一个纯化步骤,即可确定性地纠正在偏振混合态中出现的比特翻转和相位翻转错误,极大地增强了该方案的实验可行性。A deterministic entanglement purification protocol(EPP)for polarization decohered Greenberger-Horne-Zeilinger(GHZ)state is presented based on linear optical elements such as polarization beam splitter and half-wave plate.The proposed EPP makes use of spatial entanglement as an additional resource to purify polarization entanglement,and its essence is to transfer the bit-flip and phase-flip errors from polarization degree of freedom(DOF)to spatial one using the methods of linear optics and hyper-entanglement.The entanglement purification scheme can be implemented without knowing any parameters of the low-entanglement GHZ state to be purified,without converting phase flip errors to bit flips for purification,introducing the nonlinear effects.According to the proposed EPP,just in a purification step,both the bit-flip and phase-flip errors in the polarization mixed states can be deterministically corrected by using additional entanglement DOF in spatial mode,which greatly enhances the experimental feasibility of this scheme.

关 键 词：量子光学 纠缠纯化 量子通信 超纠缠 

分 类 号：O431.2[机械工程—光学工程]