N粒子部分纠缠态的量子受控传递

Controlled Quantum Teleportation of N-Particle Partly Entangled State

由于制备与传输中的环境耦合,现实中的纠缠态大部分是非最大纠缠态.在研究现有量子受控传递方案的基础上,提出了一种利用非最大纠缠态作为量子通道来概率地传输N粒子部分纠缠态的量子控制方案.在该方案中,利用非最大(N+2)-粒子GHZ态作为量子通道,在发送者进行一次Bell基测量、N-1次Hadamard门操作及|0〉和|1〉基测量,控制者实施一次Hadamard门操作及|0〉和|1〉基测量之后,接收者根据他们的测量结果,再进行一些适当的幺正变换以及一些必要的投影测量就实现了N粒子未知量子态的受控传递.该方案是一种基于非最大纠缠态的概率受控的隐形传态方案,并且成功的概率为2|a|2.

Most of quantum states in reality are non-maximal entangled states due to environmental coupling in preparation and transmission. A controlled method is presented for N-particle partly entangled state teleportation using non-maximally entangled quantum channel. In the proposed approach, a non-maximally entangled （N ＋ 2）-particle state is utilized as the quantum channel, one of the particles is selected as the controlling particle. The sender makes Bell states measurement once, Hadamard operations and ｜0〉 ＆ ｜1 〉 states measurements for N-1 times, and the controller performs a Hadamard measurement, whereafter the receiver makes appropriate unitary transformations and necessary projection measurements based on the sender＇s and controller＇ s measurement results, then the controlled teleportation of N-particle unknown quantum state is achieved. The method is a controlled quantum teleportation scheme based on non-maximally entangled state with certain odds and the success probability is 2｜a｜^2