量子纠缠态的普适远程克隆  

Universal telecloning of quantum entangled states

作　　者：李艳玲[1] 冯健[1] 於亚飞[2] 

机构地区：[1]聊城大学物理科学与信息工程学院 [2]华南师范大学光子信息技术实验室,广州510006

出　　处：《物理学报》2007年第12期6797-6802,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10574060;10404007);山东省自然科学基金(批准号:Y2004A09)资助的课题.~~

摘　　要：提出一种任意两粒子纠缠态1→2普适远程克隆方案.此方案仅需一个特殊的四粒子纠缠态作为量子信道,就可使处于空间不同位置的两个接收者分别以5/6的保真度得到任意输入态的近似拷贝,该保真度远高于已有方案中的保真度.将方案推广到任意两粒子纠缠态1→N(N>2)普适远程克隆的情况,可使处于不同地点的N个接收者分别以(2N+1)/(3N)的保真度得到输入态的近似拷贝.另外,提出一种以上述单个特殊四粒子纠缠态作为量子信道,在多目标量子比特受控非门和附加粒子的辅助下实现任意n(n≥3)粒子Greenberger-Horne-Zeilinger(GHZ)态1→2普适远程克隆的方案,并把此方案也推广到任意n粒子GHZ态1→N(N>2)普适远程克隆的情况.与已有的方案相比较,这些方案均具有节省量子信道纠缠资源、输出态保真度较高的特点.A scheme for 1→2 universal telecloning of an arbitrary two-particle entangled state using a single, particular four-particle entangled state as quantum information channel is proposed. The spatially separated two receivers respectively receive one copy of the original unknown state with the fidelity of 5/6 which is independent of the original state and is greater than the one in the currently existing schemes. Our scheme has been generalized to the case of 1→ N（ N 〉 2） universal ＂telecloning of an arbitrary two-particle entangled state. Using this scheme, the spatially separated N receivers respectively obtain one copy with the fidelity of （2N ＋ 1）/（3N） which is independent of the original state. Furthermore, we also proposed a scheme using the same fourparticle entangled state as quantum information channel with the assistance of multi-target-qubit Control-Not gate and additional qubits, for 1→2 universal telecloning of an arbitrary n-particle（ n ≥ 3） Greenberger-Home-Zeilinger （GHZ） state. This scheme is also generalized into the situation of 1→ N（ N 〉 2） telecloning of an arbitrary n-particle GHZ state. Compared with previous proposals, our schemes require a reduced amount of entangled states as quantum channels to accomplish the task of universal telecloning of entangled state with better fidelity.

关 键 词：量子纠缠态 普适远程克隆 保真度 

分 类 号：O413[理学—理论物理]