基于1→2相位协变克隆之逆的同时量子信息集中

Simultaneous Remote Information Concentration Based on the Inverse of 1→2 Phase Covariant Cloning

提出以4粒子Cluster态和一个3粒子纠缠态作为信道,在控制者许可的情况下同时将2个1→2相位协变克隆态集中回原始态的协议.协议中,空间分离的4方对手中的粒子作Bell测量,并将测量结果以经典通信的方式告诉给控制者和2个恢复方.在控制者的允许下,当信道为最大纠缠态时,2个恢复者只需各自对手中的粒子执行适当的酉操作即可恢复原始态,协议最后成功的概率为1;当信道为非最大纠缠态时,2个恢复者需要各自引入辅助粒子,并施行投影测量,就能以一定的概率恢复原始态,协议最后成功的概率与信道的参数有关.

A protocol is proposed,in which a four-particle cluster state and a three-particle entangled state are used as channels,and two 1→2 phase covariant clones are centralized back to the original state at the same time with the permission of the controller.In the protocol,four separated parties perform Bell measurements on their qubits respectively and communicate the measurements to the controller and two recuperators in a classical way.With the controller’s permission,when the channels are maximally entangled states,the two recuperators can restore the original state only by performing appropriate unitary operations on their own qubits.The probability of the success of the protocol is 1.When the channels are non-maximally entangled states,the two recuperators need to introduce auxiliary particles and perform projection measurement respectively,where they can restore the original state with a certain probability.The probability of the success of the protocol depends on the parameters of the channel.